Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 19.6s
Alternatives: 17
Speedup: 0.8×

Specification

?
\[\begin{array}{l} \\ \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))
double code(double x, double y, double z, double t, double a) {
	return ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    code = ((log((x + y)) + log(z)) - t) + ((a - 0.5d0) * log(t))
end function
public static double code(double x, double y, double z, double t, double a) {
	return ((Math.log((x + y)) + Math.log(z)) - t) + ((a - 0.5) * Math.log(t));
}
def code(x, y, z, t, a):
	return ((math.log((x + y)) + math.log(z)) - t) + ((a - 0.5) * math.log(t))
function code(x, y, z, t, a)
	return Float64(Float64(Float64(log(Float64(x + y)) + log(z)) - t) + Float64(Float64(a - 0.5) * log(t)))
end
function tmp = code(x, y, z, t, a)
	tmp = ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
end
code[x_, y_, z_, t_, a_] := N[(N[(N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 17 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))
double code(double x, double y, double z, double t, double a) {
	return ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    code = ((log((x + y)) + log(z)) - t) + ((a - 0.5d0) * log(t))
end function
public static double code(double x, double y, double z, double t, double a) {
	return ((Math.log((x + y)) + Math.log(z)) - t) + ((a - 0.5) * Math.log(t));
}
def code(x, y, z, t, a):
	return ((math.log((x + y)) + math.log(z)) - t) + ((a - 0.5) * math.log(t))
function code(x, y, z, t, a)
	return Float64(Float64(Float64(log(Float64(x + y)) + log(z)) - t) + Float64(Float64(a - 0.5) * log(t)))
end
function tmp = code(x, y, z, t, a)
	tmp = ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
end
code[x_, y_, z_, t_, a_] := N[(N[(N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t
\end{array}

Alternative 1: 99.6% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right) \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (+ (log (+ x y)) (- (fma (+ a -0.5) (log t) (log z)) t)))
double code(double x, double y, double z, double t, double a) {
	return log((x + y)) + (fma((a + -0.5), log(t), log(z)) - t);
}
function code(x, y, z, t, a)
	return Float64(log(Float64(x + y)) + Float64(fma(Float64(a + -0.5), log(t), log(z)) - t))
end
code[x_, y_, z_, t_, a_] := N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)
\end{array}
Derivation
  1. Initial program 99.5%

    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
  2. Step-by-step derivation
    1. associate--l+99.5%

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    2. associate-+l+99.5%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
    3. +-commutative99.5%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
    4. associate-+r-99.5%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
    5. fma-def99.5%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
    6. sub-neg99.5%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
    7. metadata-eval99.5%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
  4. Final simplification99.5%

    \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right) \]

Alternative 2: 74.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := a \cdot \log t\\ \mathbf{if}\;a - 0.5 \leq -2000000:\\ \;\;\;\;\left(\log y + t_1\right) - t\\ \mathbf{elif}\;a - 0.5 \leq -0.4:\\ \;\;\;\;\left(\log y + \left(\log z + -0.5 \cdot \log t\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;t_1 - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (* a (log t))))
   (if (<= (- a 0.5) -2000000.0)
     (- (+ (log y) t_1) t)
     (if (<= (- a 0.5) -0.4)
       (- (+ (log y) (+ (log z) (* -0.5 (log t)))) t)
       (- t_1 t)))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = a * log(t);
	double tmp;
	if ((a - 0.5) <= -2000000.0) {
		tmp = (log(y) + t_1) - t;
	} else if ((a - 0.5) <= -0.4) {
		tmp = (log(y) + (log(z) + (-0.5 * log(t)))) - t;
	} else {
		tmp = t_1 - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: t_1
    real(8) :: tmp
    t_1 = a * log(t)
    if ((a - 0.5d0) <= (-2000000.0d0)) then
        tmp = (log(y) + t_1) - t
    else if ((a - 0.5d0) <= (-0.4d0)) then
        tmp = (log(y) + (log(z) + ((-0.5d0) * log(t)))) - t
    else
        tmp = t_1 - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = a * Math.log(t);
	double tmp;
	if ((a - 0.5) <= -2000000.0) {
		tmp = (Math.log(y) + t_1) - t;
	} else if ((a - 0.5) <= -0.4) {
		tmp = (Math.log(y) + (Math.log(z) + (-0.5 * Math.log(t)))) - t;
	} else {
		tmp = t_1 - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = a * math.log(t)
	tmp = 0
	if (a - 0.5) <= -2000000.0:
		tmp = (math.log(y) + t_1) - t
	elif (a - 0.5) <= -0.4:
		tmp = (math.log(y) + (math.log(z) + (-0.5 * math.log(t)))) - t
	else:
		tmp = t_1 - t
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(a * log(t))
	tmp = 0.0
	if (Float64(a - 0.5) <= -2000000.0)
		tmp = Float64(Float64(log(y) + t_1) - t);
	elseif (Float64(a - 0.5) <= -0.4)
		tmp = Float64(Float64(log(y) + Float64(log(z) + Float64(-0.5 * log(t)))) - t);
	else
		tmp = Float64(t_1 - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = a * log(t);
	tmp = 0.0;
	if ((a - 0.5) <= -2000000.0)
		tmp = (log(y) + t_1) - t;
	elseif ((a - 0.5) <= -0.4)
		tmp = (log(y) + (log(z) + (-0.5 * log(t)))) - t;
	else
		tmp = t_1 - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(a - 0.5), $MachinePrecision], -2000000.0], N[(N[(N[Log[y], $MachinePrecision] + t$95$1), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[N[(a - 0.5), $MachinePrecision], -0.4], N[(N[(N[Log[y], $MachinePrecision] + N[(N[Log[z], $MachinePrecision] + N[(-0.5 * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(t$95$1 - t), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := a \cdot \log t\\
\mathbf{if}\;a - 0.5 \leq -2000000:\\
\;\;\;\;\left(\log y + t_1\right) - t\\

\mathbf{elif}\;a - 0.5 \leq -0.4:\\
\;\;\;\;\left(\log y + \left(\log z + -0.5 \cdot \log t\right)\right) - t\\

\mathbf{else}:\\
\;\;\;\;t_1 - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (-.f64 a 1/2) < -2e6

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.7%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.7%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.7%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.7%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.7%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.7%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.7%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.7%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around inf 98.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
    5. Step-by-step derivation
      1. *-commutative98.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    6. Simplified98.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    7. Taylor expanded in x around 0 72.8%

      \[\leadsto \color{blue}{\left(\log y + a \cdot \log t\right) - t} \]
    8. Step-by-step derivation
      1. log-pow5.6%

        \[\leadsto \left(\log y + \color{blue}{\log \left({t}^{a}\right)}\right) - t \]
      2. associate--l+5.6%

        \[\leadsto \color{blue}{\log y + \left(\log \left({t}^{a}\right) - t\right)} \]
      3. remove-double-neg5.6%

        \[\leadsto \color{blue}{\left(-\left(-\log y\right)\right)} + \left(\log \left({t}^{a}\right) - t\right) \]
      4. log-rec5.6%

        \[\leadsto \left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \left(\log \left({t}^{a}\right) - t\right) \]
      5. mul-1-neg5.6%

        \[\leadsto \color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \left(\log \left({t}^{a}\right) - t\right) \]
      6. associate--l+5.6%

        \[\leadsto \color{blue}{\left(-1 \cdot \log \left(\frac{1}{y}\right) + \log \left({t}^{a}\right)\right) - t} \]
      7. log-pow72.8%

        \[\leadsto \left(-1 \cdot \log \left(\frac{1}{y}\right) + \color{blue}{a \cdot \log t}\right) - t \]
      8. mul-1-neg72.8%

        \[\leadsto \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} + a \cdot \log t\right) - t \]
      9. log-rec72.8%

        \[\leadsto \left(\left(-\color{blue}{\left(-\log y\right)}\right) + a \cdot \log t\right) - t \]
      10. remove-double-neg72.8%

        \[\leadsto \left(\color{blue}{\log y} + a \cdot \log t\right) - t \]
      11. *-commutative72.8%

        \[\leadsto \left(\log y + \color{blue}{\log t \cdot a}\right) - t \]
    9. Simplified72.8%

      \[\leadsto \color{blue}{\left(\log y + \log t \cdot a\right) - t} \]

    if -2e6 < (-.f64 a 1/2) < -0.40000000000000002

    1. Initial program 99.3%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.3%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.3%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.3%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.3%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.3%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.3%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.3%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in x around 0 61.6%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
    5. Taylor expanded in a around 0 61.4%

      \[\leadsto \left(\log y + \color{blue}{\left(\log z + -0.5 \cdot \log t\right)}\right) - t \]
    6. Step-by-step derivation
      1. *-commutative61.4%

        \[\leadsto \left(\log y + \left(\log z + \color{blue}{\log t \cdot -0.5}\right)\right) - t \]
    7. Simplified61.4%

      \[\leadsto \left(\log y + \color{blue}{\left(\log z + \log t \cdot -0.5\right)}\right) - t \]

    if -0.40000000000000002 < (-.f64 a 1/2)

    1. Initial program 99.6%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 65.9%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg65.9%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec65.9%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg65.9%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative65.9%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+65.9%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg65.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec65.9%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg65.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified65.9%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around inf 99.6%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. neg-mul-199.6%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified99.6%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    8. Taylor expanded in t around 0 99.6%

      \[\leadsto \color{blue}{-1 \cdot t + \log t \cdot \left(a - 0.5\right)} \]
    9. Step-by-step derivation
      1. mul-1-neg99.6%

        \[\leadsto \color{blue}{\left(-t\right)} + \log t \cdot \left(a - 0.5\right) \]
      2. +-commutative99.6%

        \[\leadsto \color{blue}{\log t \cdot \left(a - 0.5\right) + \left(-t\right)} \]
      3. sub-neg99.6%

        \[\leadsto \log t \cdot \color{blue}{\left(a + \left(-0.5\right)\right)} + \left(-t\right) \]
      4. metadata-eval99.6%

        \[\leadsto \log t \cdot \left(a + \color{blue}{-0.5}\right) + \left(-t\right) \]
      5. +-commutative99.6%

        \[\leadsto \log t \cdot \color{blue}{\left(-0.5 + a\right)} + \left(-t\right) \]
      6. distribute-rgt-out99.6%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right)} + \left(-t\right) \]
      7. sub-neg99.6%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right) - t} \]
      8. distribute-rgt-out99.6%

        \[\leadsto \color{blue}{\log t \cdot \left(-0.5 + a\right)} - t \]
      9. +-commutative99.6%

        \[\leadsto \log t \cdot \color{blue}{\left(a + -0.5\right)} - t \]
    10. Simplified99.6%

      \[\leadsto \color{blue}{\log t \cdot \left(a + -0.5\right) - t} \]
    11. Taylor expanded in a around inf 99.6%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    12. Step-by-step derivation
      1. *-commutative99.6%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    13. Simplified99.6%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  3. Recombined 3 regimes into one program.
  4. Final simplification74.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -2000000:\\ \;\;\;\;\left(\log y + a \cdot \log t\right) - t\\ \mathbf{elif}\;a - 0.5 \leq -0.4:\\ \;\;\;\;\left(\log y + \left(\log z + -0.5 \cdot \log t\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \]

Alternative 3: 74.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := a \cdot \log t\\ \mathbf{if}\;a \leq -14000:\\ \;\;\;\;\left(\log y + t_1\right) - t\\ \mathbf{elif}\;a \leq 0.96:\\ \;\;\;\;\left(\log z + \left(\log y - t\right)\right) + -0.5 \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;t_1 - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (* a (log t))))
   (if (<= a -14000.0)
     (- (+ (log y) t_1) t)
     (if (<= a 0.96)
       (+ (+ (log z) (- (log y) t)) (* -0.5 (log t)))
       (- t_1 t)))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = a * log(t);
	double tmp;
	if (a <= -14000.0) {
		tmp = (log(y) + t_1) - t;
	} else if (a <= 0.96) {
		tmp = (log(z) + (log(y) - t)) + (-0.5 * log(t));
	} else {
		tmp = t_1 - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: t_1
    real(8) :: tmp
    t_1 = a * log(t)
    if (a <= (-14000.0d0)) then
        tmp = (log(y) + t_1) - t
    else if (a <= 0.96d0) then
        tmp = (log(z) + (log(y) - t)) + ((-0.5d0) * log(t))
    else
        tmp = t_1 - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = a * Math.log(t);
	double tmp;
	if (a <= -14000.0) {
		tmp = (Math.log(y) + t_1) - t;
	} else if (a <= 0.96) {
		tmp = (Math.log(z) + (Math.log(y) - t)) + (-0.5 * Math.log(t));
	} else {
		tmp = t_1 - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = a * math.log(t)
	tmp = 0
	if a <= -14000.0:
		tmp = (math.log(y) + t_1) - t
	elif a <= 0.96:
		tmp = (math.log(z) + (math.log(y) - t)) + (-0.5 * math.log(t))
	else:
		tmp = t_1 - t
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(a * log(t))
	tmp = 0.0
	if (a <= -14000.0)
		tmp = Float64(Float64(log(y) + t_1) - t);
	elseif (a <= 0.96)
		tmp = Float64(Float64(log(z) + Float64(log(y) - t)) + Float64(-0.5 * log(t)));
	else
		tmp = Float64(t_1 - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = a * log(t);
	tmp = 0.0;
	if (a <= -14000.0)
		tmp = (log(y) + t_1) - t;
	elseif (a <= 0.96)
		tmp = (log(z) + (log(y) - t)) + (-0.5 * log(t));
	else
		tmp = t_1 - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[a, -14000.0], N[(N[(N[Log[y], $MachinePrecision] + t$95$1), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[a, 0.96], N[(N[(N[Log[z], $MachinePrecision] + N[(N[Log[y], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision] + N[(-0.5 * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(t$95$1 - t), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := a \cdot \log t\\
\mathbf{if}\;a \leq -14000:\\
\;\;\;\;\left(\log y + t_1\right) - t\\

\mathbf{elif}\;a \leq 0.96:\\
\;\;\;\;\left(\log z + \left(\log y - t\right)\right) + -0.5 \cdot \log t\\

\mathbf{else}:\\
\;\;\;\;t_1 - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if a < -14000

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.7%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.7%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.7%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.7%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.7%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.7%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.7%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.7%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around inf 98.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
    5. Step-by-step derivation
      1. *-commutative98.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    6. Simplified98.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    7. Taylor expanded in x around 0 72.8%

      \[\leadsto \color{blue}{\left(\log y + a \cdot \log t\right) - t} \]
    8. Step-by-step derivation
      1. log-pow5.6%

        \[\leadsto \left(\log y + \color{blue}{\log \left({t}^{a}\right)}\right) - t \]
      2. associate--l+5.6%

        \[\leadsto \color{blue}{\log y + \left(\log \left({t}^{a}\right) - t\right)} \]
      3. remove-double-neg5.6%

        \[\leadsto \color{blue}{\left(-\left(-\log y\right)\right)} + \left(\log \left({t}^{a}\right) - t\right) \]
      4. log-rec5.6%

        \[\leadsto \left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \left(\log \left({t}^{a}\right) - t\right) \]
      5. mul-1-neg5.6%

        \[\leadsto \color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \left(\log \left({t}^{a}\right) - t\right) \]
      6. associate--l+5.6%

        \[\leadsto \color{blue}{\left(-1 \cdot \log \left(\frac{1}{y}\right) + \log \left({t}^{a}\right)\right) - t} \]
      7. log-pow72.8%

        \[\leadsto \left(-1 \cdot \log \left(\frac{1}{y}\right) + \color{blue}{a \cdot \log t}\right) - t \]
      8. mul-1-neg72.8%

        \[\leadsto \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} + a \cdot \log t\right) - t \]
      9. log-rec72.8%

        \[\leadsto \left(\left(-\color{blue}{\left(-\log y\right)}\right) + a \cdot \log t\right) - t \]
      10. remove-double-neg72.8%

        \[\leadsto \left(\color{blue}{\log y} + a \cdot \log t\right) - t \]
      11. *-commutative72.8%

        \[\leadsto \left(\log y + \color{blue}{\log t \cdot a}\right) - t \]
    9. Simplified72.8%

      \[\leadsto \color{blue}{\left(\log y + \log t \cdot a\right) - t} \]

    if -14000 < a < 0.95999999999999996

    1. Initial program 99.3%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 61.6%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg61.6%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec61.6%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg61.6%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative61.6%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+61.6%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg61.6%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec61.6%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg61.6%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified61.6%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in a around 0 61.4%

      \[\leadsto \left(\log z + \left(\log y - t\right)\right) + \color{blue}{-0.5 \cdot \log t} \]

    if 0.95999999999999996 < a

    1. Initial program 99.6%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 65.9%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg65.9%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec65.9%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg65.9%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative65.9%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+65.9%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg65.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec65.9%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg65.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified65.9%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around inf 99.6%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. neg-mul-199.6%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified99.6%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    8. Taylor expanded in t around 0 99.6%

      \[\leadsto \color{blue}{-1 \cdot t + \log t \cdot \left(a - 0.5\right)} \]
    9. Step-by-step derivation
      1. mul-1-neg99.6%

        \[\leadsto \color{blue}{\left(-t\right)} + \log t \cdot \left(a - 0.5\right) \]
      2. +-commutative99.6%

        \[\leadsto \color{blue}{\log t \cdot \left(a - 0.5\right) + \left(-t\right)} \]
      3. sub-neg99.6%

        \[\leadsto \log t \cdot \color{blue}{\left(a + \left(-0.5\right)\right)} + \left(-t\right) \]
      4. metadata-eval99.6%

        \[\leadsto \log t \cdot \left(a + \color{blue}{-0.5}\right) + \left(-t\right) \]
      5. +-commutative99.6%

        \[\leadsto \log t \cdot \color{blue}{\left(-0.5 + a\right)} + \left(-t\right) \]
      6. distribute-rgt-out99.6%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right)} + \left(-t\right) \]
      7. sub-neg99.6%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right) - t} \]
      8. distribute-rgt-out99.6%

        \[\leadsto \color{blue}{\log t \cdot \left(-0.5 + a\right)} - t \]
      9. +-commutative99.6%

        \[\leadsto \log t \cdot \color{blue}{\left(a + -0.5\right)} - t \]
    10. Simplified99.6%

      \[\leadsto \color{blue}{\log t \cdot \left(a + -0.5\right) - t} \]
    11. Taylor expanded in a around inf 99.6%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    12. Step-by-step derivation
      1. *-commutative99.6%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    13. Simplified99.6%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  3. Recombined 3 regimes into one program.
  4. Final simplification74.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -14000:\\ \;\;\;\;\left(\log y + a \cdot \log t\right) - t\\ \mathbf{elif}\;a \leq 0.96:\\ \;\;\;\;\left(\log z + \left(\log y - t\right)\right) + -0.5 \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \]

Alternative 4: 71.7% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := a \cdot \log t\\ \mathbf{if}\;a \leq -14000:\\ \;\;\;\;\left(\log y + t_1\right) - t\\ \mathbf{elif}\;a \leq 0.006:\\ \;\;\;\;\left(\log y + \log \left(z \cdot {t}^{-0.5}\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;t_1 - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (* a (log t))))
   (if (<= a -14000.0)
     (- (+ (log y) t_1) t)
     (if (<= a 0.006) (- (+ (log y) (log (* z (pow t -0.5)))) t) (- t_1 t)))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = a * log(t);
	double tmp;
	if (a <= -14000.0) {
		tmp = (log(y) + t_1) - t;
	} else if (a <= 0.006) {
		tmp = (log(y) + log((z * pow(t, -0.5)))) - t;
	} else {
		tmp = t_1 - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: t_1
    real(8) :: tmp
    t_1 = a * log(t)
    if (a <= (-14000.0d0)) then
        tmp = (log(y) + t_1) - t
    else if (a <= 0.006d0) then
        tmp = (log(y) + log((z * (t ** (-0.5d0))))) - t
    else
        tmp = t_1 - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = a * Math.log(t);
	double tmp;
	if (a <= -14000.0) {
		tmp = (Math.log(y) + t_1) - t;
	} else if (a <= 0.006) {
		tmp = (Math.log(y) + Math.log((z * Math.pow(t, -0.5)))) - t;
	} else {
		tmp = t_1 - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = a * math.log(t)
	tmp = 0
	if a <= -14000.0:
		tmp = (math.log(y) + t_1) - t
	elif a <= 0.006:
		tmp = (math.log(y) + math.log((z * math.pow(t, -0.5)))) - t
	else:
		tmp = t_1 - t
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(a * log(t))
	tmp = 0.0
	if (a <= -14000.0)
		tmp = Float64(Float64(log(y) + t_1) - t);
	elseif (a <= 0.006)
		tmp = Float64(Float64(log(y) + log(Float64(z * (t ^ -0.5)))) - t);
	else
		tmp = Float64(t_1 - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = a * log(t);
	tmp = 0.0;
	if (a <= -14000.0)
		tmp = (log(y) + t_1) - t;
	elseif (a <= 0.006)
		tmp = (log(y) + log((z * (t ^ -0.5)))) - t;
	else
		tmp = t_1 - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[a, -14000.0], N[(N[(N[Log[y], $MachinePrecision] + t$95$1), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[a, 0.006], N[(N[(N[Log[y], $MachinePrecision] + N[Log[N[(z * N[Power[t, -0.5], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(t$95$1 - t), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := a \cdot \log t\\
\mathbf{if}\;a \leq -14000:\\
\;\;\;\;\left(\log y + t_1\right) - t\\

\mathbf{elif}\;a \leq 0.006:\\
\;\;\;\;\left(\log y + \log \left(z \cdot {t}^{-0.5}\right)\right) - t\\

\mathbf{else}:\\
\;\;\;\;t_1 - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if a < -14000

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.7%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.7%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.7%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.7%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.7%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.7%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.7%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.7%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around inf 98.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
    5. Step-by-step derivation
      1. *-commutative98.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    6. Simplified98.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    7. Taylor expanded in x around 0 72.8%

      \[\leadsto \color{blue}{\left(\log y + a \cdot \log t\right) - t} \]
    8. Step-by-step derivation
      1. log-pow5.6%

        \[\leadsto \left(\log y + \color{blue}{\log \left({t}^{a}\right)}\right) - t \]
      2. associate--l+5.6%

        \[\leadsto \color{blue}{\log y + \left(\log \left({t}^{a}\right) - t\right)} \]
      3. remove-double-neg5.6%

        \[\leadsto \color{blue}{\left(-\left(-\log y\right)\right)} + \left(\log \left({t}^{a}\right) - t\right) \]
      4. log-rec5.6%

        \[\leadsto \left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \left(\log \left({t}^{a}\right) - t\right) \]
      5. mul-1-neg5.6%

        \[\leadsto \color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \left(\log \left({t}^{a}\right) - t\right) \]
      6. associate--l+5.6%

        \[\leadsto \color{blue}{\left(-1 \cdot \log \left(\frac{1}{y}\right) + \log \left({t}^{a}\right)\right) - t} \]
      7. log-pow72.8%

        \[\leadsto \left(-1 \cdot \log \left(\frac{1}{y}\right) + \color{blue}{a \cdot \log t}\right) - t \]
      8. mul-1-neg72.8%

        \[\leadsto \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} + a \cdot \log t\right) - t \]
      9. log-rec72.8%

        \[\leadsto \left(\left(-\color{blue}{\left(-\log y\right)}\right) + a \cdot \log t\right) - t \]
      10. remove-double-neg72.8%

        \[\leadsto \left(\color{blue}{\log y} + a \cdot \log t\right) - t \]
      11. *-commutative72.8%

        \[\leadsto \left(\log y + \color{blue}{\log t \cdot a}\right) - t \]
    9. Simplified72.8%

      \[\leadsto \color{blue}{\left(\log y + \log t \cdot a\right) - t} \]

    if -14000 < a < 0.0060000000000000001

    1. Initial program 99.3%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.3%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.3%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.3%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.3%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.3%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.3%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.3%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in x around 0 61.6%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
    5. Taylor expanded in a around 0 61.4%

      \[\leadsto \left(\log y + \color{blue}{\left(\log z + -0.5 \cdot \log t\right)}\right) - t \]
    6. Step-by-step derivation
      1. *-commutative61.4%

        \[\leadsto \left(\log y + \left(\log z + \color{blue}{\log t \cdot -0.5}\right)\right) - t \]
    7. Simplified61.4%

      \[\leadsto \left(\log y + \color{blue}{\left(\log z + \log t \cdot -0.5\right)}\right) - t \]
    8. Step-by-step derivation
      1. add-log-exp61.4%

        \[\leadsto \left(\log y + \left(\log z + \color{blue}{\log \left(e^{\log t \cdot -0.5}\right)}\right)\right) - t \]
      2. sum-log56.3%

        \[\leadsto \left(\log y + \color{blue}{\log \left(z \cdot e^{\log t \cdot -0.5}\right)}\right) - t \]
      3. exp-to-pow56.3%

        \[\leadsto \left(\log y + \log \left(z \cdot \color{blue}{{t}^{-0.5}}\right)\right) - t \]
    9. Applied egg-rr56.3%

      \[\leadsto \left(\log y + \color{blue}{\log \left(z \cdot {t}^{-0.5}\right)}\right) - t \]

    if 0.0060000000000000001 < a

    1. Initial program 99.6%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 65.9%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg65.9%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec65.9%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg65.9%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative65.9%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+65.9%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg65.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec65.9%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg65.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified65.9%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around inf 99.6%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. neg-mul-199.6%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified99.6%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    8. Taylor expanded in t around 0 99.6%

      \[\leadsto \color{blue}{-1 \cdot t + \log t \cdot \left(a - 0.5\right)} \]
    9. Step-by-step derivation
      1. mul-1-neg99.6%

        \[\leadsto \color{blue}{\left(-t\right)} + \log t \cdot \left(a - 0.5\right) \]
      2. +-commutative99.6%

        \[\leadsto \color{blue}{\log t \cdot \left(a - 0.5\right) + \left(-t\right)} \]
      3. sub-neg99.6%

        \[\leadsto \log t \cdot \color{blue}{\left(a + \left(-0.5\right)\right)} + \left(-t\right) \]
      4. metadata-eval99.6%

        \[\leadsto \log t \cdot \left(a + \color{blue}{-0.5}\right) + \left(-t\right) \]
      5. +-commutative99.6%

        \[\leadsto \log t \cdot \color{blue}{\left(-0.5 + a\right)} + \left(-t\right) \]
      6. distribute-rgt-out99.6%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right)} + \left(-t\right) \]
      7. sub-neg99.6%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right) - t} \]
      8. distribute-rgt-out99.6%

        \[\leadsto \color{blue}{\log t \cdot \left(-0.5 + a\right)} - t \]
      9. +-commutative99.6%

        \[\leadsto \log t \cdot \color{blue}{\left(a + -0.5\right)} - t \]
    10. Simplified99.6%

      \[\leadsto \color{blue}{\log t \cdot \left(a + -0.5\right) - t} \]
    11. Taylor expanded in a around inf 99.6%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    12. Step-by-step derivation
      1. *-commutative99.6%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    13. Simplified99.6%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  3. Recombined 3 regimes into one program.
  4. Final simplification71.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -14000:\\ \;\;\;\;\left(\log y + a \cdot \log t\right) - t\\ \mathbf{elif}\;a \leq 0.006:\\ \;\;\;\;\left(\log y + \log \left(z \cdot {t}^{-0.5}\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \]

Alternative 5: 69.2% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(\log z + \left(\log y - t\right)\right) + \log t \cdot \left(a - 0.5\right) \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (+ (+ (log z) (- (log y) t)) (* (log t) (- a 0.5))))
double code(double x, double y, double z, double t, double a) {
	return (log(z) + (log(y) - t)) + (log(t) * (a - 0.5));
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    code = (log(z) + (log(y) - t)) + (log(t) * (a - 0.5d0))
end function
public static double code(double x, double y, double z, double t, double a) {
	return (Math.log(z) + (Math.log(y) - t)) + (Math.log(t) * (a - 0.5));
}
def code(x, y, z, t, a):
	return (math.log(z) + (math.log(y) - t)) + (math.log(t) * (a - 0.5))
function code(x, y, z, t, a)
	return Float64(Float64(log(z) + Float64(log(y) - t)) + Float64(log(t) * Float64(a - 0.5)))
end
function tmp = code(x, y, z, t, a)
	tmp = (log(z) + (log(y) - t)) + (log(t) * (a - 0.5));
end
code[x_, y_, z_, t_, a_] := N[(N[(N[Log[z], $MachinePrecision] + N[(N[Log[y], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\log z + \left(\log y - t\right)\right) + \log t \cdot \left(a - 0.5\right)
\end{array}
Derivation
  1. Initial program 99.5%

    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
  2. Taylor expanded in x around 0 66.4%

    \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
  3. Step-by-step derivation
    1. remove-double-neg66.4%

      \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. log-rec66.4%

      \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    3. mul-1-neg66.4%

      \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    4. +-commutative66.4%

      \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
    5. associate--l+66.4%

      \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    6. mul-1-neg66.4%

      \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    7. log-rec66.4%

      \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    8. remove-double-neg66.4%

      \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
  4. Simplified66.4%

    \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
  5. Final simplification66.4%

    \[\leadsto \left(\log z + \left(\log y - t\right)\right) + \log t \cdot \left(a - 0.5\right) \]

Alternative 6: 65.6% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := a \cdot \log t\\ \mathbf{if}\;a - 0.5 \leq -2000000:\\ \;\;\;\;\left(\log y + t_1\right) - t\\ \mathbf{elif}\;a - 0.5 \leq -0.4:\\ \;\;\;\;\log \left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;t_1 - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (* a (log t))))
   (if (<= (- a 0.5) -2000000.0)
     (- (+ (log y) t_1) t)
     (if (<= (- a 0.5) -0.4) (- (log (* y (* z (pow t -0.5)))) t) (- t_1 t)))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = a * log(t);
	double tmp;
	if ((a - 0.5) <= -2000000.0) {
		tmp = (log(y) + t_1) - t;
	} else if ((a - 0.5) <= -0.4) {
		tmp = log((y * (z * pow(t, -0.5)))) - t;
	} else {
		tmp = t_1 - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: t_1
    real(8) :: tmp
    t_1 = a * log(t)
    if ((a - 0.5d0) <= (-2000000.0d0)) then
        tmp = (log(y) + t_1) - t
    else if ((a - 0.5d0) <= (-0.4d0)) then
        tmp = log((y * (z * (t ** (-0.5d0))))) - t
    else
        tmp = t_1 - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = a * Math.log(t);
	double tmp;
	if ((a - 0.5) <= -2000000.0) {
		tmp = (Math.log(y) + t_1) - t;
	} else if ((a - 0.5) <= -0.4) {
		tmp = Math.log((y * (z * Math.pow(t, -0.5)))) - t;
	} else {
		tmp = t_1 - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = a * math.log(t)
	tmp = 0
	if (a - 0.5) <= -2000000.0:
		tmp = (math.log(y) + t_1) - t
	elif (a - 0.5) <= -0.4:
		tmp = math.log((y * (z * math.pow(t, -0.5)))) - t
	else:
		tmp = t_1 - t
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(a * log(t))
	tmp = 0.0
	if (Float64(a - 0.5) <= -2000000.0)
		tmp = Float64(Float64(log(y) + t_1) - t);
	elseif (Float64(a - 0.5) <= -0.4)
		tmp = Float64(log(Float64(y * Float64(z * (t ^ -0.5)))) - t);
	else
		tmp = Float64(t_1 - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = a * log(t);
	tmp = 0.0;
	if ((a - 0.5) <= -2000000.0)
		tmp = (log(y) + t_1) - t;
	elseif ((a - 0.5) <= -0.4)
		tmp = log((y * (z * (t ^ -0.5)))) - t;
	else
		tmp = t_1 - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(a - 0.5), $MachinePrecision], -2000000.0], N[(N[(N[Log[y], $MachinePrecision] + t$95$1), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[N[(a - 0.5), $MachinePrecision], -0.4], N[(N[Log[N[(y * N[(z * N[Power[t, -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision], N[(t$95$1 - t), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := a \cdot \log t\\
\mathbf{if}\;a - 0.5 \leq -2000000:\\
\;\;\;\;\left(\log y + t_1\right) - t\\

\mathbf{elif}\;a - 0.5 \leq -0.4:\\
\;\;\;\;\log \left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right) - t\\

\mathbf{else}:\\
\;\;\;\;t_1 - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (-.f64 a 1/2) < -2e6

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.7%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.7%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.7%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.7%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.7%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.7%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.7%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.7%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around inf 98.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
    5. Step-by-step derivation
      1. *-commutative98.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    6. Simplified98.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    7. Taylor expanded in x around 0 72.8%

      \[\leadsto \color{blue}{\left(\log y + a \cdot \log t\right) - t} \]
    8. Step-by-step derivation
      1. log-pow5.6%

        \[\leadsto \left(\log y + \color{blue}{\log \left({t}^{a}\right)}\right) - t \]
      2. associate--l+5.6%

        \[\leadsto \color{blue}{\log y + \left(\log \left({t}^{a}\right) - t\right)} \]
      3. remove-double-neg5.6%

        \[\leadsto \color{blue}{\left(-\left(-\log y\right)\right)} + \left(\log \left({t}^{a}\right) - t\right) \]
      4. log-rec5.6%

        \[\leadsto \left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \left(\log \left({t}^{a}\right) - t\right) \]
      5. mul-1-neg5.6%

        \[\leadsto \color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \left(\log \left({t}^{a}\right) - t\right) \]
      6. associate--l+5.6%

        \[\leadsto \color{blue}{\left(-1 \cdot \log \left(\frac{1}{y}\right) + \log \left({t}^{a}\right)\right) - t} \]
      7. log-pow72.8%

        \[\leadsto \left(-1 \cdot \log \left(\frac{1}{y}\right) + \color{blue}{a \cdot \log t}\right) - t \]
      8. mul-1-neg72.8%

        \[\leadsto \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} + a \cdot \log t\right) - t \]
      9. log-rec72.8%

        \[\leadsto \left(\left(-\color{blue}{\left(-\log y\right)}\right) + a \cdot \log t\right) - t \]
      10. remove-double-neg72.8%

        \[\leadsto \left(\color{blue}{\log y} + a \cdot \log t\right) - t \]
      11. *-commutative72.8%

        \[\leadsto \left(\log y + \color{blue}{\log t \cdot a}\right) - t \]
    9. Simplified72.8%

      \[\leadsto \color{blue}{\left(\log y + \log t \cdot a\right) - t} \]

    if -2e6 < (-.f64 a 1/2) < -0.40000000000000002

    1. Initial program 99.3%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.3%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.3%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.3%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.3%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.3%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.3%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.3%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around 0 98.3%

      \[\leadsto \color{blue}{\left(\log z + \left(\log \left(x + y\right) + -0.5 \cdot \log t\right)\right) - t} \]
    5. Step-by-step derivation
      1. associate-+r+98.4%

        \[\leadsto \color{blue}{\left(\left(\log z + \log \left(x + y\right)\right) + -0.5 \cdot \log t\right)} - t \]
      2. log-prod80.7%

        \[\leadsto \left(\color{blue}{\log \left(z \cdot \left(x + y\right)\right)} + -0.5 \cdot \log t\right) - t \]
      3. +-commutative80.7%

        \[\leadsto \left(\log \left(z \cdot \color{blue}{\left(y + x\right)}\right) + -0.5 \cdot \log t\right) - t \]
    6. Simplified80.7%

      \[\leadsto \color{blue}{\left(\log \left(z \cdot \left(y + x\right)\right) + -0.5 \cdot \log t\right) - t} \]
    7. Taylor expanded in y around inf 61.3%

      \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) + -0.5 \cdot \log t\right)\right)} - t \]
    8. Step-by-step derivation
      1. associate-+r+61.4%

        \[\leadsto \color{blue}{\left(\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right) + -0.5 \cdot \log t\right)} - t \]
      2. +-commutative61.4%

        \[\leadsto \left(\color{blue}{\left(-1 \cdot \log \left(\frac{1}{y}\right) + \log z\right)} + -0.5 \cdot \log t\right) - t \]
      3. mul-1-neg61.4%

        \[\leadsto \left(\left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} + \log z\right) + -0.5 \cdot \log t\right) - t \]
      4. log-rec61.4%

        \[\leadsto \left(\left(\left(-\color{blue}{\left(-\log y\right)}\right) + \log z\right) + -0.5 \cdot \log t\right) - t \]
      5. remove-double-neg61.4%

        \[\leadsto \left(\left(\color{blue}{\log y} + \log z\right) + -0.5 \cdot \log t\right) - t \]
      6. log-prod46.2%

        \[\leadsto \left(\color{blue}{\log \left(y \cdot z\right)} + -0.5 \cdot \log t\right) - t \]
      7. +-commutative46.2%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + \log \left(y \cdot z\right)\right)} - t \]
      8. *-commutative46.2%

        \[\leadsto \left(\color{blue}{\log t \cdot -0.5} + \log \left(y \cdot z\right)\right) - t \]
    9. Simplified46.2%

      \[\leadsto \color{blue}{\left(\log t \cdot -0.5 + \log \left(y \cdot z\right)\right)} - t \]
    10. Step-by-step derivation
      1. +-commutative46.2%

        \[\leadsto \color{blue}{\left(\log \left(y \cdot z\right) + \log t \cdot -0.5\right)} - t \]
      2. log-prod61.4%

        \[\leadsto \left(\color{blue}{\left(\log y + \log z\right)} + \log t \cdot -0.5\right) - t \]
      3. associate-+r+61.4%

        \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot -0.5\right)\right)} - t \]
      4. add-log-exp56.2%

        \[\leadsto \left(\log y + \color{blue}{\log \left(e^{\log z + \log t \cdot -0.5}\right)}\right) - t \]
      5. sum-log43.8%

        \[\leadsto \color{blue}{\log \left(y \cdot e^{\log z + \log t \cdot -0.5}\right)} - t \]
      6. exp-sum43.9%

        \[\leadsto \log \left(y \cdot \color{blue}{\left(e^{\log z} \cdot e^{\log t \cdot -0.5}\right)}\right) - t \]
      7. add-exp-log44.0%

        \[\leadsto \log \left(y \cdot \left(\color{blue}{z} \cdot e^{\log t \cdot -0.5}\right)\right) - t \]
      8. exp-to-pow44.1%

        \[\leadsto \log \left(y \cdot \left(z \cdot \color{blue}{{t}^{-0.5}}\right)\right) - t \]
    11. Applied egg-rr44.1%

      \[\leadsto \color{blue}{\log \left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right)} - t \]

    if -0.40000000000000002 < (-.f64 a 1/2)

    1. Initial program 99.6%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 65.9%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg65.9%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec65.9%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg65.9%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative65.9%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+65.9%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg65.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec65.9%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg65.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified65.9%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around inf 99.6%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. neg-mul-199.6%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified99.6%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    8. Taylor expanded in t around 0 99.6%

      \[\leadsto \color{blue}{-1 \cdot t + \log t \cdot \left(a - 0.5\right)} \]
    9. Step-by-step derivation
      1. mul-1-neg99.6%

        \[\leadsto \color{blue}{\left(-t\right)} + \log t \cdot \left(a - 0.5\right) \]
      2. +-commutative99.6%

        \[\leadsto \color{blue}{\log t \cdot \left(a - 0.5\right) + \left(-t\right)} \]
      3. sub-neg99.6%

        \[\leadsto \log t \cdot \color{blue}{\left(a + \left(-0.5\right)\right)} + \left(-t\right) \]
      4. metadata-eval99.6%

        \[\leadsto \log t \cdot \left(a + \color{blue}{-0.5}\right) + \left(-t\right) \]
      5. +-commutative99.6%

        \[\leadsto \log t \cdot \color{blue}{\left(-0.5 + a\right)} + \left(-t\right) \]
      6. distribute-rgt-out99.6%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right)} + \left(-t\right) \]
      7. sub-neg99.6%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right) - t} \]
      8. distribute-rgt-out99.6%

        \[\leadsto \color{blue}{\log t \cdot \left(-0.5 + a\right)} - t \]
      9. +-commutative99.6%

        \[\leadsto \log t \cdot \color{blue}{\left(a + -0.5\right)} - t \]
    10. Simplified99.6%

      \[\leadsto \color{blue}{\log t \cdot \left(a + -0.5\right) - t} \]
    11. Taylor expanded in a around inf 99.6%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    12. Step-by-step derivation
      1. *-commutative99.6%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    13. Simplified99.6%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  3. Recombined 3 regimes into one program.
  4. Final simplification66.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -2000000:\\ \;\;\;\;\left(\log y + a \cdot \log t\right) - t\\ \mathbf{elif}\;a - 0.5 \leq -0.4:\\ \;\;\;\;\log \left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \]

Alternative 7: 87.0% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(a + -0.5\right) \cdot \log t - t\\ \mathbf{if}\;z \leq 6.5 \cdot 10^{+81}:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + t_1\\ \mathbf{else}:\\ \;\;\;\;t_1\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (- (* (+ a -0.5) (log t)) t)))
   (if (<= z 6.5e+81) (+ (log (* (+ x y) z)) t_1) t_1)))
double code(double x, double y, double z, double t, double a) {
	double t_1 = ((a + -0.5) * log(t)) - t;
	double tmp;
	if (z <= 6.5e+81) {
		tmp = log(((x + y) * z)) + t_1;
	} else {
		tmp = t_1;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: t_1
    real(8) :: tmp
    t_1 = ((a + (-0.5d0)) * log(t)) - t
    if (z <= 6.5d+81) then
        tmp = log(((x + y) * z)) + t_1
    else
        tmp = t_1
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = ((a + -0.5) * Math.log(t)) - t;
	double tmp;
	if (z <= 6.5e+81) {
		tmp = Math.log(((x + y) * z)) + t_1;
	} else {
		tmp = t_1;
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = ((a + -0.5) * math.log(t)) - t
	tmp = 0
	if z <= 6.5e+81:
		tmp = math.log(((x + y) * z)) + t_1
	else:
		tmp = t_1
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(Float64(Float64(a + -0.5) * log(t)) - t)
	tmp = 0.0
	if (z <= 6.5e+81)
		tmp = Float64(log(Float64(Float64(x + y) * z)) + t_1);
	else
		tmp = t_1;
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = ((a + -0.5) * log(t)) - t;
	tmp = 0.0;
	if (z <= 6.5e+81)
		tmp = log(((x + y) * z)) + t_1;
	else
		tmp = t_1;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]}, If[LessEqual[z, 6.5e+81], N[(N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision] + t$95$1), $MachinePrecision], t$95$1]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(a + -0.5\right) \cdot \log t - t\\
\mathbf{if}\;z \leq 6.5 \cdot 10^{+81}:\\
\;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + t_1\\

\mathbf{else}:\\
\;\;\;\;t_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < 6.4999999999999996e81

    1. Initial program 99.4%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate-+l-99.4%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right) - \left(t - \left(a - 0.5\right) \cdot \log t\right)} \]
      2. +-commutative99.4%

        \[\leadsto \color{blue}{\left(\log z + \log \left(x + y\right)\right)} - \left(t - \left(a - 0.5\right) \cdot \log t\right) \]
      3. sum-log95.1%

        \[\leadsto \color{blue}{\log \left(z \cdot \left(x + y\right)\right)} - \left(t - \left(a - 0.5\right) \cdot \log t\right) \]
      4. sub-neg95.1%

        \[\leadsto \log \left(z \cdot \left(x + y\right)\right) - \left(t - \color{blue}{\left(a + \left(-0.5\right)\right)} \cdot \log t\right) \]
      5. metadata-eval95.1%

        \[\leadsto \log \left(z \cdot \left(x + y\right)\right) - \left(t - \left(a + \color{blue}{-0.5}\right) \cdot \log t\right) \]
    3. Applied egg-rr95.1%

      \[\leadsto \color{blue}{\log \left(z \cdot \left(x + y\right)\right) - \left(t - \left(a + -0.5\right) \cdot \log t\right)} \]

    if 6.4999999999999996e81 < z

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 65.9%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg65.9%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec65.9%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg65.9%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative65.9%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+65.9%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg65.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec65.9%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg65.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified65.9%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around inf 85.5%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. neg-mul-185.5%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified85.5%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    8. Taylor expanded in t around 0 85.5%

      \[\leadsto \color{blue}{-1 \cdot t + \log t \cdot \left(a - 0.5\right)} \]
    9. Step-by-step derivation
      1. mul-1-neg85.5%

        \[\leadsto \color{blue}{\left(-t\right)} + \log t \cdot \left(a - 0.5\right) \]
      2. +-commutative85.5%

        \[\leadsto \color{blue}{\log t \cdot \left(a - 0.5\right) + \left(-t\right)} \]
      3. sub-neg85.5%

        \[\leadsto \log t \cdot \color{blue}{\left(a + \left(-0.5\right)\right)} + \left(-t\right) \]
      4. metadata-eval85.5%

        \[\leadsto \log t \cdot \left(a + \color{blue}{-0.5}\right) + \left(-t\right) \]
      5. +-commutative85.5%

        \[\leadsto \log t \cdot \color{blue}{\left(-0.5 + a\right)} + \left(-t\right) \]
      6. distribute-rgt-out85.5%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right)} + \left(-t\right) \]
      7. sub-neg85.5%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right) - t} \]
      8. distribute-rgt-out85.5%

        \[\leadsto \color{blue}{\log t \cdot \left(-0.5 + a\right)} - t \]
      9. +-commutative85.5%

        \[\leadsto \log t \cdot \color{blue}{\left(a + -0.5\right)} - t \]
    10. Simplified85.5%

      \[\leadsto \color{blue}{\log t \cdot \left(a + -0.5\right) - t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification91.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq 6.5 \cdot 10^{+81}:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \left(\left(a + -0.5\right) \cdot \log t - t\right)\\ \mathbf{else}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\ \end{array} \]

Alternative 8: 61.8% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 0.0115:\\ \;\;\;\;\log \left(y \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + a \cdot \log t\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 0.0115)
   (+ (log (* y z)) (* (log t) (- a 0.5)))
   (- (+ (log y) (* a (log t))) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 0.0115) {
		tmp = log((y * z)) + (log(t) * (a - 0.5));
	} else {
		tmp = (log(y) + (a * log(t))) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 0.0115d0) then
        tmp = log((y * z)) + (log(t) * (a - 0.5d0))
    else
        tmp = (log(y) + (a * log(t))) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 0.0115) {
		tmp = Math.log((y * z)) + (Math.log(t) * (a - 0.5));
	} else {
		tmp = (Math.log(y) + (a * Math.log(t))) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 0.0115:
		tmp = math.log((y * z)) + (math.log(t) * (a - 0.5))
	else:
		tmp = (math.log(y) + (a * math.log(t))) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 0.0115)
		tmp = Float64(log(Float64(y * z)) + Float64(log(t) * Float64(a - 0.5)));
	else
		tmp = Float64(Float64(log(y) + Float64(a * log(t))) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 0.0115)
		tmp = log((y * z)) + (log(t) * (a - 0.5));
	else
		tmp = (log(y) + (a * log(t))) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 0.0115], N[(N[Log[N[(y * z), $MachinePrecision]], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 0.0115:\\
\;\;\;\;\log \left(y \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;\left(\log y + a \cdot \log t\right) - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 0.0115

    1. Initial program 99.1%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 62.0%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg62.0%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec62.0%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg62.0%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative62.0%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+62.0%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg62.0%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec62.0%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg62.0%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified62.0%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around 0 61.7%

      \[\leadsto \color{blue}{\left(\log y + \log z\right)} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. log-prod49.8%

        \[\leadsto \color{blue}{\log \left(y \cdot z\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified49.8%

      \[\leadsto \color{blue}{\log \left(y \cdot z\right)} + \left(a - 0.5\right) \cdot \log t \]

    if 0.0115 < t

    1. Initial program 99.9%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.9%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.9%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.9%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.9%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.9%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.9%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around inf 99.5%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
    5. Step-by-step derivation
      1. *-commutative99.5%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    6. Simplified99.5%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    7. Taylor expanded in x around 0 70.4%

      \[\leadsto \color{blue}{\left(\log y + a \cdot \log t\right) - t} \]
    8. Step-by-step derivation
      1. log-pow32.4%

        \[\leadsto \left(\log y + \color{blue}{\log \left({t}^{a}\right)}\right) - t \]
      2. associate--l+32.4%

        \[\leadsto \color{blue}{\log y + \left(\log \left({t}^{a}\right) - t\right)} \]
      3. remove-double-neg32.4%

        \[\leadsto \color{blue}{\left(-\left(-\log y\right)\right)} + \left(\log \left({t}^{a}\right) - t\right) \]
      4. log-rec32.4%

        \[\leadsto \left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \left(\log \left({t}^{a}\right) - t\right) \]
      5. mul-1-neg32.4%

        \[\leadsto \color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \left(\log \left({t}^{a}\right) - t\right) \]
      6. associate--l+32.4%

        \[\leadsto \color{blue}{\left(-1 \cdot \log \left(\frac{1}{y}\right) + \log \left({t}^{a}\right)\right) - t} \]
      7. log-pow70.4%

        \[\leadsto \left(-1 \cdot \log \left(\frac{1}{y}\right) + \color{blue}{a \cdot \log t}\right) - t \]
      8. mul-1-neg70.4%

        \[\leadsto \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} + a \cdot \log t\right) - t \]
      9. log-rec70.4%

        \[\leadsto \left(\left(-\color{blue}{\left(-\log y\right)}\right) + a \cdot \log t\right) - t \]
      10. remove-double-neg70.4%

        \[\leadsto \left(\color{blue}{\log y} + a \cdot \log t\right) - t \]
      11. *-commutative70.4%

        \[\leadsto \left(\log y + \color{blue}{\log t \cdot a}\right) - t \]
    9. Simplified70.4%

      \[\leadsto \color{blue}{\left(\log y + \log t \cdot a\right) - t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification60.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 0.0115:\\ \;\;\;\;\log \left(y \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + a \cdot \log t\right) - t\\ \end{array} \]

Alternative 9: 73.8% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 3.4 \cdot 10^{-5}:\\ \;\;\;\;\log \left(y \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + y\right) + \left(a \cdot \log t - t\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 3.4e-5)
   (+ (log (* y z)) (* (log t) (- a 0.5)))
   (+ (log (+ x y)) (- (* a (log t)) t))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 3.4e-5) {
		tmp = log((y * z)) + (log(t) * (a - 0.5));
	} else {
		tmp = log((x + y)) + ((a * log(t)) - t);
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 3.4d-5) then
        tmp = log((y * z)) + (log(t) * (a - 0.5d0))
    else
        tmp = log((x + y)) + ((a * log(t)) - t)
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 3.4e-5) {
		tmp = Math.log((y * z)) + (Math.log(t) * (a - 0.5));
	} else {
		tmp = Math.log((x + y)) + ((a * Math.log(t)) - t);
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 3.4e-5:
		tmp = math.log((y * z)) + (math.log(t) * (a - 0.5))
	else:
		tmp = math.log((x + y)) + ((a * math.log(t)) - t)
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 3.4e-5)
		tmp = Float64(log(Float64(y * z)) + Float64(log(t) * Float64(a - 0.5)));
	else
		tmp = Float64(log(Float64(x + y)) + Float64(Float64(a * log(t)) - t));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 3.4e-5)
		tmp = log((y * z)) + (log(t) * (a - 0.5));
	else
		tmp = log((x + y)) + ((a * log(t)) - t);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 3.4e-5], N[(N[Log[N[(y * z), $MachinePrecision]], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 3.4 \cdot 10^{-5}:\\
\;\;\;\;\log \left(y \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;\log \left(x + y\right) + \left(a \cdot \log t - t\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 3.4e-5

    1. Initial program 99.1%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 62.0%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg62.0%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec62.0%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg62.0%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative62.0%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+62.0%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg62.0%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec62.0%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg62.0%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified62.0%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around 0 61.7%

      \[\leadsto \color{blue}{\left(\log y + \log z\right)} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. log-prod49.8%

        \[\leadsto \color{blue}{\log \left(y \cdot z\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified49.8%

      \[\leadsto \color{blue}{\log \left(y \cdot z\right)} + \left(a - 0.5\right) \cdot \log t \]

    if 3.4e-5 < t

    1. Initial program 99.9%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.9%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.9%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.9%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.9%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.9%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.9%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around inf 99.5%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
    5. Step-by-step derivation
      1. *-commutative99.5%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    6. Simplified99.5%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification74.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 3.4 \cdot 10^{-5}:\\ \;\;\;\;\log \left(y \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + y\right) + \left(a \cdot \log t - t\right)\\ \end{array} \]

Alternative 10: 64.1% accurate, 2.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 1.12 \cdot 10^{+20} \lor \neg \left(t \leq 3 \cdot 10^{+63}\right) \land t \leq 1.22 \cdot 10^{+100}:\\ \;\;\;\;\log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (or (<= t 1.12e+20) (and (not (<= t 3e+63)) (<= t 1.22e+100)))
   (* (log t) (- a 0.5))
   (- t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((t <= 1.12e+20) || (!(t <= 3e+63) && (t <= 1.22e+100))) {
		tmp = log(t) * (a - 0.5);
	} else {
		tmp = -t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if ((t <= 1.12d+20) .or. (.not. (t <= 3d+63)) .and. (t <= 1.22d+100)) then
        tmp = log(t) * (a - 0.5d0)
    else
        tmp = -t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((t <= 1.12e+20) || (!(t <= 3e+63) && (t <= 1.22e+100))) {
		tmp = Math.log(t) * (a - 0.5);
	} else {
		tmp = -t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if (t <= 1.12e+20) or (not (t <= 3e+63) and (t <= 1.22e+100)):
		tmp = math.log(t) * (a - 0.5)
	else:
		tmp = -t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if ((t <= 1.12e+20) || (!(t <= 3e+63) && (t <= 1.22e+100)))
		tmp = Float64(log(t) * Float64(a - 0.5));
	else
		tmp = Float64(-t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if ((t <= 1.12e+20) || (~((t <= 3e+63)) && (t <= 1.22e+100)))
		tmp = log(t) * (a - 0.5);
	else
		tmp = -t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[Or[LessEqual[t, 1.12e+20], And[N[Not[LessEqual[t, 3e+63]], $MachinePrecision], LessEqual[t, 1.22e+100]]], N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision], (-t)]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 1.12 \cdot 10^{+20} \lor \neg \left(t \leq 3 \cdot 10^{+63}\right) \land t \leq 1.22 \cdot 10^{+100}:\\
\;\;\;\;\log t \cdot \left(a - 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;-t\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 1.12e20 or 2.99999999999999999e63 < t < 1.21999999999999995e100

    1. Initial program 99.2%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 64.7%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg64.7%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec64.7%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg64.7%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative64.7%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+64.7%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg64.7%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec64.7%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg64.7%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified64.7%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around inf 65.9%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. neg-mul-165.9%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified65.9%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    8. Taylor expanded in t around 0 62.0%

      \[\leadsto \color{blue}{\log t \cdot \left(a - 0.5\right)} \]

    if 1.12e20 < t < 2.99999999999999999e63 or 1.21999999999999995e100 < t

    1. Initial program 99.9%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.9%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.9%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.9%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.9%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.9%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.9%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in t around inf 77.2%

      \[\leadsto \color{blue}{-1 \cdot t} \]
    5. Step-by-step derivation
      1. neg-mul-177.2%

        \[\leadsto \color{blue}{-t} \]
    6. Simplified77.2%

      \[\leadsto \color{blue}{-t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification68.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 1.12 \cdot 10^{+20} \lor \neg \left(t \leq 3 \cdot 10^{+63}\right) \land t \leq 1.22 \cdot 10^{+100}:\\ \;\;\;\;\log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]

Alternative 11: 66.4% accurate, 2.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -2000000 \lor \neg \left(a \leq 10^{+37}\right):\\ \;\;\;\;a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + y\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (or (<= a -2000000.0) (not (<= a 1e+37)))
   (* a (log t))
   (- (log (+ x y)) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a <= -2000000.0) || !(a <= 1e+37)) {
		tmp = a * log(t);
	} else {
		tmp = log((x + y)) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if ((a <= (-2000000.0d0)) .or. (.not. (a <= 1d+37))) then
        tmp = a * log(t)
    else
        tmp = log((x + y)) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a <= -2000000.0) || !(a <= 1e+37)) {
		tmp = a * Math.log(t);
	} else {
		tmp = Math.log((x + y)) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if (a <= -2000000.0) or not (a <= 1e+37):
		tmp = a * math.log(t)
	else:
		tmp = math.log((x + y)) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if ((a <= -2000000.0) || !(a <= 1e+37))
		tmp = Float64(a * log(t));
	else
		tmp = Float64(log(Float64(x + y)) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if ((a <= -2000000.0) || ~((a <= 1e+37)))
		tmp = a * log(t);
	else
		tmp = log((x + y)) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[Or[LessEqual[a, -2000000.0], N[Not[LessEqual[a, 1e+37]], $MachinePrecision]], N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision], N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -2000000 \lor \neg \left(a \leq 10^{+37}\right):\\
\;\;\;\;a \cdot \log t\\

\mathbf{else}:\\
\;\;\;\;\log \left(x + y\right) - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -2e6 or 9.99999999999999954e36 < a

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 69.9%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg69.9%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec69.9%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg69.9%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative69.9%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+69.9%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg69.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec69.9%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg69.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified69.9%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in a around inf 79.2%

      \[\leadsto \color{blue}{a \cdot \log t} \]
    6. Step-by-step derivation
      1. *-commutative79.2%

        \[\leadsto \color{blue}{\log t \cdot a} \]
    7. Simplified79.2%

      \[\leadsto \color{blue}{\log t \cdot a} \]

    if -2e6 < a < 9.99999999999999954e36

    1. Initial program 99.3%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.3%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.3%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.3%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.3%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.3%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.3%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.3%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around inf 57.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
    5. Step-by-step derivation
      1. *-commutative57.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    6. Simplified57.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    7. Taylor expanded in a around 0 55.6%

      \[\leadsto \color{blue}{\log \left(x + y\right) - t} \]
    8. Step-by-step derivation
      1. +-commutative55.6%

        \[\leadsto \log \color{blue}{\left(y + x\right)} - t \]
    9. Simplified55.6%

      \[\leadsto \color{blue}{\log \left(y + x\right) - t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification67.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -2000000 \lor \neg \left(a \leq 10^{+37}\right):\\ \;\;\;\;a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + y\right) - t\\ \end{array} \]

Alternative 12: 77.6% accurate, 2.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 0.0195:\\ \;\;\;\;t + \left(a + -0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 0.0195) (+ t (* (+ a -0.5) (log t))) (- (* a (log t)) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 0.0195) {
		tmp = t + ((a + -0.5) * log(t));
	} else {
		tmp = (a * log(t)) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 0.0195d0) then
        tmp = t + ((a + (-0.5d0)) * log(t))
    else
        tmp = (a * log(t)) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 0.0195) {
		tmp = t + ((a + -0.5) * Math.log(t));
	} else {
		tmp = (a * Math.log(t)) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 0.0195:
		tmp = t + ((a + -0.5) * math.log(t))
	else:
		tmp = (a * math.log(t)) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 0.0195)
		tmp = Float64(t + Float64(Float64(a + -0.5) * log(t)));
	else
		tmp = Float64(Float64(a * log(t)) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 0.0195)
		tmp = t + ((a + -0.5) * log(t));
	else
		tmp = (a * log(t)) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 0.0195], N[(t + N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 0.0195:\\
\;\;\;\;t + \left(a + -0.5\right) \cdot \log t\\

\mathbf{else}:\\
\;\;\;\;a \cdot \log t - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 0.0195

    1. Initial program 99.1%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 62.0%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg62.0%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec62.0%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg62.0%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative62.0%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+62.0%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg62.0%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec62.0%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg62.0%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified62.0%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around inf 60.0%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. neg-mul-160.0%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified60.0%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    8. Taylor expanded in t around 0 60.0%

      \[\leadsto \color{blue}{-1 \cdot t + \log t \cdot \left(a - 0.5\right)} \]
    9. Step-by-step derivation
      1. mul-1-neg60.0%

        \[\leadsto \color{blue}{\left(-t\right)} + \log t \cdot \left(a - 0.5\right) \]
      2. +-commutative60.0%

        \[\leadsto \color{blue}{\log t \cdot \left(a - 0.5\right) + \left(-t\right)} \]
      3. sub-neg60.0%

        \[\leadsto \log t \cdot \color{blue}{\left(a + \left(-0.5\right)\right)} + \left(-t\right) \]
      4. metadata-eval60.0%

        \[\leadsto \log t \cdot \left(a + \color{blue}{-0.5}\right) + \left(-t\right) \]
      5. +-commutative60.0%

        \[\leadsto \log t \cdot \color{blue}{\left(-0.5 + a\right)} + \left(-t\right) \]
      6. distribute-rgt-out60.0%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right)} + \left(-t\right) \]
      7. sub-neg60.0%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right) - t} \]
      8. distribute-rgt-out60.0%

        \[\leadsto \color{blue}{\log t \cdot \left(-0.5 + a\right)} - t \]
      9. +-commutative60.0%

        \[\leadsto \log t \cdot \color{blue}{\left(a + -0.5\right)} - t \]
    10. Simplified60.0%

      \[\leadsto \color{blue}{\log t \cdot \left(a + -0.5\right) - t} \]
    11. Step-by-step derivation
      1. sub-neg60.0%

        \[\leadsto \color{blue}{\log t \cdot \left(a + -0.5\right) + \left(-t\right)} \]
      2. add-sqr-sqrt0.0%

        \[\leadsto \log t \cdot \left(a + -0.5\right) + \color{blue}{\sqrt{-t} \cdot \sqrt{-t}} \]
      3. sqrt-unprod60.0%

        \[\leadsto \log t \cdot \left(a + -0.5\right) + \color{blue}{\sqrt{\left(-t\right) \cdot \left(-t\right)}} \]
      4. sqr-neg60.0%

        \[\leadsto \log t \cdot \left(a + -0.5\right) + \sqrt{\color{blue}{t \cdot t}} \]
      5. sqrt-unprod60.0%

        \[\leadsto \log t \cdot \left(a + -0.5\right) + \color{blue}{\sqrt{t} \cdot \sqrt{t}} \]
      6. add-sqr-sqrt60.0%

        \[\leadsto \log t \cdot \left(a + -0.5\right) + \color{blue}{t} \]
    12. Applied egg-rr60.0%

      \[\leadsto \color{blue}{\log t \cdot \left(a + -0.5\right) + t} \]

    if 0.0195 < t

    1. Initial program 99.9%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 70.8%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg70.8%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec70.8%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg70.8%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative70.8%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+70.8%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg70.8%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec70.8%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg70.8%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified70.8%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around inf 99.5%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. neg-mul-199.5%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified99.5%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    8. Taylor expanded in t around 0 99.5%

      \[\leadsto \color{blue}{-1 \cdot t + \log t \cdot \left(a - 0.5\right)} \]
    9. Step-by-step derivation
      1. mul-1-neg99.5%

        \[\leadsto \color{blue}{\left(-t\right)} + \log t \cdot \left(a - 0.5\right) \]
      2. +-commutative99.5%

        \[\leadsto \color{blue}{\log t \cdot \left(a - 0.5\right) + \left(-t\right)} \]
      3. sub-neg99.5%

        \[\leadsto \log t \cdot \color{blue}{\left(a + \left(-0.5\right)\right)} + \left(-t\right) \]
      4. metadata-eval99.5%

        \[\leadsto \log t \cdot \left(a + \color{blue}{-0.5}\right) + \left(-t\right) \]
      5. +-commutative99.5%

        \[\leadsto \log t \cdot \color{blue}{\left(-0.5 + a\right)} + \left(-t\right) \]
      6. distribute-rgt-out99.5%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right)} + \left(-t\right) \]
      7. sub-neg99.5%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right) - t} \]
      8. distribute-rgt-out99.5%

        \[\leadsto \color{blue}{\log t \cdot \left(-0.5 + a\right)} - t \]
      9. +-commutative99.5%

        \[\leadsto \log t \cdot \color{blue}{\left(a + -0.5\right)} - t \]
    10. Simplified99.5%

      \[\leadsto \color{blue}{\log t \cdot \left(a + -0.5\right) - t} \]
    11. Taylor expanded in a around inf 99.5%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    12. Step-by-step derivation
      1. *-commutative99.5%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    13. Simplified99.5%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification79.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 0.0195:\\ \;\;\;\;t + \left(a + -0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \]

Alternative 13: 63.3% accurate, 2.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -2000000 \lor \neg \left(a \leq 10^{+37}\right):\\ \;\;\;\;a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (or (<= a -2000000.0) (not (<= a 1e+37))) (* a (log t)) (- t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a <= -2000000.0) || !(a <= 1e+37)) {
		tmp = a * log(t);
	} else {
		tmp = -t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if ((a <= (-2000000.0d0)) .or. (.not. (a <= 1d+37))) then
        tmp = a * log(t)
    else
        tmp = -t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a <= -2000000.0) || !(a <= 1e+37)) {
		tmp = a * Math.log(t);
	} else {
		tmp = -t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if (a <= -2000000.0) or not (a <= 1e+37):
		tmp = a * math.log(t)
	else:
		tmp = -t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if ((a <= -2000000.0) || !(a <= 1e+37))
		tmp = Float64(a * log(t));
	else
		tmp = Float64(-t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if ((a <= -2000000.0) || ~((a <= 1e+37)))
		tmp = a * log(t);
	else
		tmp = -t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[Or[LessEqual[a, -2000000.0], N[Not[LessEqual[a, 1e+37]], $MachinePrecision]], N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision], (-t)]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -2000000 \lor \neg \left(a \leq 10^{+37}\right):\\
\;\;\;\;a \cdot \log t\\

\mathbf{else}:\\
\;\;\;\;-t\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -2e6 or 9.99999999999999954e36 < a

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 69.9%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg69.9%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec69.9%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg69.9%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative69.9%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+69.9%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg69.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec69.9%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg69.9%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified69.9%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in a around inf 79.2%

      \[\leadsto \color{blue}{a \cdot \log t} \]
    6. Step-by-step derivation
      1. *-commutative79.2%

        \[\leadsto \color{blue}{\log t \cdot a} \]
    7. Simplified79.2%

      \[\leadsto \color{blue}{\log t \cdot a} \]

    if -2e6 < a < 9.99999999999999954e36

    1. Initial program 99.3%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.3%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.3%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.3%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.3%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.3%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.3%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.3%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in t around inf 50.3%

      \[\leadsto \color{blue}{-1 \cdot t} \]
    5. Step-by-step derivation
      1. neg-mul-150.3%

        \[\leadsto \color{blue}{-t} \]
    6. Simplified50.3%

      \[\leadsto \color{blue}{-t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification65.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -2000000 \lor \neg \left(a \leq 10^{+37}\right):\\ \;\;\;\;a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]

Alternative 14: 77.6% accurate, 2.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 0.00045:\\ \;\;\;\;\log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 0.00045) (* (log t) (- a 0.5)) (- (* a (log t)) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 0.00045) {
		tmp = log(t) * (a - 0.5);
	} else {
		tmp = (a * log(t)) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 0.00045d0) then
        tmp = log(t) * (a - 0.5d0)
    else
        tmp = (a * log(t)) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 0.00045) {
		tmp = Math.log(t) * (a - 0.5);
	} else {
		tmp = (a * Math.log(t)) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 0.00045:
		tmp = math.log(t) * (a - 0.5)
	else:
		tmp = (a * math.log(t)) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 0.00045)
		tmp = Float64(log(t) * Float64(a - 0.5));
	else
		tmp = Float64(Float64(a * log(t)) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 0.00045)
		tmp = log(t) * (a - 0.5);
	else
		tmp = (a * log(t)) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 0.00045], N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 0.00045:\\
\;\;\;\;\log t \cdot \left(a - 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;a \cdot \log t - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 4.4999999999999999e-4

    1. Initial program 99.1%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 62.0%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg62.0%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec62.0%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg62.0%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative62.0%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+62.0%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg62.0%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec62.0%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg62.0%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified62.0%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around inf 60.0%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. neg-mul-160.0%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified60.0%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    8. Taylor expanded in t around 0 60.0%

      \[\leadsto \color{blue}{\log t \cdot \left(a - 0.5\right)} \]

    if 4.4999999999999999e-4 < t

    1. Initial program 99.9%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 70.8%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg70.8%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec70.8%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg70.8%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative70.8%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+70.8%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg70.8%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec70.8%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg70.8%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified70.8%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around inf 99.5%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. neg-mul-199.5%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified99.5%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    8. Taylor expanded in t around 0 99.5%

      \[\leadsto \color{blue}{-1 \cdot t + \log t \cdot \left(a - 0.5\right)} \]
    9. Step-by-step derivation
      1. mul-1-neg99.5%

        \[\leadsto \color{blue}{\left(-t\right)} + \log t \cdot \left(a - 0.5\right) \]
      2. +-commutative99.5%

        \[\leadsto \color{blue}{\log t \cdot \left(a - 0.5\right) + \left(-t\right)} \]
      3. sub-neg99.5%

        \[\leadsto \log t \cdot \color{blue}{\left(a + \left(-0.5\right)\right)} + \left(-t\right) \]
      4. metadata-eval99.5%

        \[\leadsto \log t \cdot \left(a + \color{blue}{-0.5}\right) + \left(-t\right) \]
      5. +-commutative99.5%

        \[\leadsto \log t \cdot \color{blue}{\left(-0.5 + a\right)} + \left(-t\right) \]
      6. distribute-rgt-out99.5%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right)} + \left(-t\right) \]
      7. sub-neg99.5%

        \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right) - t} \]
      8. distribute-rgt-out99.5%

        \[\leadsto \color{blue}{\log t \cdot \left(-0.5 + a\right)} - t \]
      9. +-commutative99.5%

        \[\leadsto \log t \cdot \color{blue}{\left(a + -0.5\right)} - t \]
    10. Simplified99.5%

      \[\leadsto \color{blue}{\log t \cdot \left(a + -0.5\right) - t} \]
    11. Taylor expanded in a around inf 99.5%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    12. Step-by-step derivation
      1. *-commutative99.5%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    13. Simplified99.5%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification79.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 0.00045:\\ \;\;\;\;\log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \]

Alternative 15: 77.6% accurate, 2.9× speedup?

\[\begin{array}{l} \\ \left(a + -0.5\right) \cdot \log t - t \end{array} \]
(FPCore (x y z t a) :precision binary64 (- (* (+ a -0.5) (log t)) t))
double code(double x, double y, double z, double t, double a) {
	return ((a + -0.5) * log(t)) - t;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    code = ((a + (-0.5d0)) * log(t)) - t
end function
public static double code(double x, double y, double z, double t, double a) {
	return ((a + -0.5) * Math.log(t)) - t;
}
def code(x, y, z, t, a):
	return ((a + -0.5) * math.log(t)) - t
function code(x, y, z, t, a)
	return Float64(Float64(Float64(a + -0.5) * log(t)) - t)
end
function tmp = code(x, y, z, t, a)
	tmp = ((a + -0.5) * log(t)) - t;
end
code[x_, y_, z_, t_, a_] := N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]
\begin{array}{l}

\\
\left(a + -0.5\right) \cdot \log t - t
\end{array}
Derivation
  1. Initial program 99.5%

    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
  2. Taylor expanded in x around 0 66.4%

    \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
  3. Step-by-step derivation
    1. remove-double-neg66.4%

      \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. log-rec66.4%

      \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    3. mul-1-neg66.4%

      \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    4. +-commutative66.4%

      \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
    5. associate--l+66.4%

      \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    6. mul-1-neg66.4%

      \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    7. log-rec66.4%

      \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    8. remove-double-neg66.4%

      \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
  4. Simplified66.4%

    \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
  5. Taylor expanded in t around inf 79.6%

    \[\leadsto \color{blue}{-1 \cdot t} + \left(a - 0.5\right) \cdot \log t \]
  6. Step-by-step derivation
    1. neg-mul-179.6%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
  7. Simplified79.6%

    \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
  8. Taylor expanded in t around 0 79.6%

    \[\leadsto \color{blue}{-1 \cdot t + \log t \cdot \left(a - 0.5\right)} \]
  9. Step-by-step derivation
    1. mul-1-neg79.6%

      \[\leadsto \color{blue}{\left(-t\right)} + \log t \cdot \left(a - 0.5\right) \]
    2. +-commutative79.6%

      \[\leadsto \color{blue}{\log t \cdot \left(a - 0.5\right) + \left(-t\right)} \]
    3. sub-neg79.6%

      \[\leadsto \log t \cdot \color{blue}{\left(a + \left(-0.5\right)\right)} + \left(-t\right) \]
    4. metadata-eval79.6%

      \[\leadsto \log t \cdot \left(a + \color{blue}{-0.5}\right) + \left(-t\right) \]
    5. +-commutative79.6%

      \[\leadsto \log t \cdot \color{blue}{\left(-0.5 + a\right)} + \left(-t\right) \]
    6. distribute-rgt-out79.6%

      \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right)} + \left(-t\right) \]
    7. sub-neg79.6%

      \[\leadsto \color{blue}{\left(-0.5 \cdot \log t + a \cdot \log t\right) - t} \]
    8. distribute-rgt-out79.6%

      \[\leadsto \color{blue}{\log t \cdot \left(-0.5 + a\right)} - t \]
    9. +-commutative79.6%

      \[\leadsto \log t \cdot \color{blue}{\left(a + -0.5\right)} - t \]
  10. Simplified79.6%

    \[\leadsto \color{blue}{\log t \cdot \left(a + -0.5\right) - t} \]
  11. Final simplification79.6%

    \[\leadsto \left(a + -0.5\right) \cdot \log t - t \]

Alternative 16: 40.5% accurate, 3.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 0.92:\\ \;\;\;\;-0.5 \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 0.92) (* -0.5 (log t)) (- t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 0.92) {
		tmp = -0.5 * log(t);
	} else {
		tmp = -t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 0.92d0) then
        tmp = (-0.5d0) * log(t)
    else
        tmp = -t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 0.92) {
		tmp = -0.5 * Math.log(t);
	} else {
		tmp = -t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 0.92:
		tmp = -0.5 * math.log(t)
	else:
		tmp = -t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 0.92)
		tmp = Float64(-0.5 * log(t));
	else
		tmp = Float64(-t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 0.92)
		tmp = -0.5 * log(t);
	else
		tmp = -t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 0.92], N[(-0.5 * N[Log[t], $MachinePrecision]), $MachinePrecision], (-t)]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 0.92:\\
\;\;\;\;-0.5 \cdot \log t\\

\mathbf{else}:\\
\;\;\;\;-t\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 0.92000000000000004

    1. Initial program 99.1%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 62.3%

      \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
    3. Step-by-step derivation
      1. remove-double-neg62.3%

        \[\leadsto \left(\left(\color{blue}{\left(-\left(-\log y\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. log-rec62.3%

        \[\leadsto \left(\left(\left(-\color{blue}{\log \left(\frac{1}{y}\right)}\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. mul-1-neg62.3%

        \[\leadsto \left(\left(\color{blue}{-1 \cdot \log \left(\frac{1}{y}\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      4. +-commutative62.3%

        \[\leadsto \left(\color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      5. associate--l+62.3%

        \[\leadsto \color{blue}{\left(\log z + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      6. mul-1-neg62.3%

        \[\leadsto \left(\log z + \left(\color{blue}{\left(-\log \left(\frac{1}{y}\right)\right)} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      7. log-rec62.3%

        \[\leadsto \left(\log z + \left(\left(-\color{blue}{\left(-\log y\right)}\right) - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
      8. remove-double-neg62.3%

        \[\leadsto \left(\log z + \left(\color{blue}{\log y} - t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Simplified62.3%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in t around inf 60.3%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a - 0.5\right) \cdot \log t \]
    6. Step-by-step derivation
      1. neg-mul-160.3%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    7. Simplified60.3%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
    8. Taylor expanded in t around 0 60.3%

      \[\leadsto \color{blue}{\log t \cdot \left(a - 0.5\right)} \]
    9. Taylor expanded in a around 0 8.4%

      \[\leadsto \color{blue}{-0.5 \cdot \log t} \]
    10. Step-by-step derivation
      1. *-commutative8.4%

        \[\leadsto \color{blue}{\log t \cdot -0.5} \]
    11. Simplified8.4%

      \[\leadsto \color{blue}{\log t \cdot -0.5} \]

    if 0.92000000000000004 < t

    1. Initial program 99.9%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.9%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.9%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.9%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.9%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.9%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.9%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in t around inf 68.9%

      \[\leadsto \color{blue}{-1 \cdot t} \]
    5. Step-by-step derivation
      1. neg-mul-168.9%

        \[\leadsto \color{blue}{-t} \]
    6. Simplified68.9%

      \[\leadsto \color{blue}{-t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification38.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 0.92:\\ \;\;\;\;-0.5 \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]

Alternative 17: 37.5% accurate, 156.5× speedup?

\[\begin{array}{l} \\ -t \end{array} \]
(FPCore (x y z t a) :precision binary64 (- t))
double code(double x, double y, double z, double t, double a) {
	return -t;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    code = -t
end function
public static double code(double x, double y, double z, double t, double a) {
	return -t;
}
def code(x, y, z, t, a):
	return -t
function code(x, y, z, t, a)
	return Float64(-t)
end
function tmp = code(x, y, z, t, a)
	tmp = -t;
end
code[x_, y_, z_, t_, a_] := (-t)
\begin{array}{l}

\\
-t
\end{array}
Derivation
  1. Initial program 99.5%

    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
  2. Step-by-step derivation
    1. associate--l+99.5%

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    2. associate-+l+99.5%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
    3. +-commutative99.5%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
    4. associate-+r-99.5%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
    5. fma-def99.5%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
    6. sub-neg99.5%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
    7. metadata-eval99.5%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
  4. Taylor expanded in t around inf 35.3%

    \[\leadsto \color{blue}{-1 \cdot t} \]
  5. Step-by-step derivation
    1. neg-mul-135.3%

      \[\leadsto \color{blue}{-t} \]
  6. Simplified35.3%

    \[\leadsto \color{blue}{-t} \]
  7. Final simplification35.3%

    \[\leadsto -t \]

Developer target: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right) \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (+ (log (+ x y)) (+ (- (log z) t) (* (- a 0.5) (log t)))))
double code(double x, double y, double z, double t, double a) {
	return log((x + y)) + ((log(z) - t) + ((a - 0.5) * log(t)));
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    code = log((x + y)) + ((log(z) - t) + ((a - 0.5d0) * log(t)))
end function
public static double code(double x, double y, double z, double t, double a) {
	return Math.log((x + y)) + ((Math.log(z) - t) + ((a - 0.5) * Math.log(t)));
}
def code(x, y, z, t, a):
	return math.log((x + y)) + ((math.log(z) - t) + ((a - 0.5) * math.log(t)))
function code(x, y, z, t, a)
	return Float64(log(Float64(x + y)) + Float64(Float64(log(z) - t) + Float64(Float64(a - 0.5) * log(t))))
end
function tmp = code(x, y, z, t, a)
	tmp = log((x + y)) + ((log(z) - t) + ((a - 0.5) * log(t)));
end
code[x_, y_, z_, t_, a_] := N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[(N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)
\end{array}

Reproduce

?
herbie shell --seed 2023271 
(FPCore (x y z t a)
  :name "Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2"
  :precision binary64

  :herbie-target
  (+ (log (+ x y)) (+ (- (log z) t) (* (- a 0.5) (log t))))

  (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))