Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 22.5s
Alternatives: 15
Speedup: 1.0×

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 15 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, 1.0× speedup?

\[\begin{array}{l} \\ \left(\log z - t\right) + \left(\log \left(y + x\right) - \log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (+ (- (log z) t) (- (log (+ y x)) (* (log (/ 1.0 t)) (- a 0.5)))))
double code(double x, double y, double z, double t, double a) {
	return (log(z) - t) + (log((y + x)) - (log((1.0 / 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) - t) + (log((y + x)) - (log((1.0d0 / t)) * (a - 0.5d0)))
end function
public static double code(double x, double y, double z, double t, double a) {
	return (Math.log(z) - t) + (Math.log((y + x)) - (Math.log((1.0 / t)) * (a - 0.5)));
}
def code(x, y, z, t, a):
	return (math.log(z) - t) + (math.log((y + x)) - (math.log((1.0 / t)) * (a - 0.5)))
function code(x, y, z, t, a)
	return Float64(Float64(log(z) - t) + Float64(log(Float64(y + x)) - Float64(log(Float64(1.0 / t)) * Float64(a - 0.5))))
end
function tmp = code(x, y, z, t, a)
	tmp = (log(z) - t) + (log((y + x)) - (log((1.0 / t)) * (a - 0.5)));
end
code[x_, y_, z_, t_, a_] := N[(N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision] + N[(N[Log[N[(y + x), $MachinePrecision]], $MachinePrecision] - N[(N[Log[N[(1.0 / t), $MachinePrecision]], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\log z - t\right) + \left(\log \left(y + x\right) - \log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right)
\end{array}
Derivation
  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. +-commutative99.7%

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

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

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

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

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

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

    \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
  4. Taylor expanded in t around inf 99.7%

    \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
  5. Final simplification99.7%

    \[\leadsto \left(\log z - t\right) + \left(\log \left(y + x\right) - \log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) \]

Alternative 2: 98.1% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \log z - t\\ \mathbf{if}\;a - 0.5 \leq -500000:\\ \;\;\;\;t_1 + a \cdot \log t\\ \mathbf{elif}\;a - 0.5 \leq -0.5:\\ \;\;\;\;t_1 + \left(\log \left(y + x\right) + -0.5 \cdot \log t\right)\\ \mathbf{else}:\\ \;\;\;\;t_1 - \log \left(\frac{1}{t}\right) \cdot a\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (- (log z) t)))
   (if (<= (- a 0.5) -500000.0)
     (+ t_1 (* a (log t)))
     (if (<= (- a 0.5) -0.5)
       (+ t_1 (+ (log (+ y x)) (* -0.5 (log t))))
       (- t_1 (* (log (/ 1.0 t)) a))))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = log(z) - t;
	double tmp;
	if ((a - 0.5) <= -500000.0) {
		tmp = t_1 + (a * log(t));
	} else if ((a - 0.5) <= -0.5) {
		tmp = t_1 + (log((y + x)) + (-0.5 * log(t)));
	} else {
		tmp = t_1 - (log((1.0 / t)) * a);
	}
	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 = log(z) - t
    if ((a - 0.5d0) <= (-500000.0d0)) then
        tmp = t_1 + (a * log(t))
    else if ((a - 0.5d0) <= (-0.5d0)) then
        tmp = t_1 + (log((y + x)) + ((-0.5d0) * log(t)))
    else
        tmp = t_1 - (log((1.0d0 / t)) * a)
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = Math.log(z) - t;
	double tmp;
	if ((a - 0.5) <= -500000.0) {
		tmp = t_1 + (a * Math.log(t));
	} else if ((a - 0.5) <= -0.5) {
		tmp = t_1 + (Math.log((y + x)) + (-0.5 * Math.log(t)));
	} else {
		tmp = t_1 - (Math.log((1.0 / t)) * a);
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = math.log(z) - t
	tmp = 0
	if (a - 0.5) <= -500000.0:
		tmp = t_1 + (a * math.log(t))
	elif (a - 0.5) <= -0.5:
		tmp = t_1 + (math.log((y + x)) + (-0.5 * math.log(t)))
	else:
		tmp = t_1 - (math.log((1.0 / t)) * a)
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(log(z) - t)
	tmp = 0.0
	if (Float64(a - 0.5) <= -500000.0)
		tmp = Float64(t_1 + Float64(a * log(t)));
	elseif (Float64(a - 0.5) <= -0.5)
		tmp = Float64(t_1 + Float64(log(Float64(y + x)) + Float64(-0.5 * log(t))));
	else
		tmp = Float64(t_1 - Float64(log(Float64(1.0 / t)) * a));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = log(z) - t;
	tmp = 0.0;
	if ((a - 0.5) <= -500000.0)
		tmp = t_1 + (a * log(t));
	elseif ((a - 0.5) <= -0.5)
		tmp = t_1 + (log((y + x)) + (-0.5 * log(t)));
	else
		tmp = t_1 - (log((1.0 / t)) * a);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision]}, If[LessEqual[N[(a - 0.5), $MachinePrecision], -500000.0], N[(t$95$1 + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[N[(a - 0.5), $MachinePrecision], -0.5], N[(t$95$1 + N[(N[Log[N[(y + x), $MachinePrecision]], $MachinePrecision] + N[(-0.5 * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(t$95$1 - N[(N[Log[N[(1.0 / t), $MachinePrecision]], $MachinePrecision] * a), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \log z - t\\
\mathbf{if}\;a - 0.5 \leq -500000:\\
\;\;\;\;t_1 + a \cdot \log t\\

\mathbf{elif}\;a - 0.5 \leq -0.5:\\
\;\;\;\;t_1 + \left(\log \left(y + x\right) + -0.5 \cdot \log t\right)\\

\mathbf{else}:\\
\;\;\;\;t_1 - \log \left(\frac{1}{t}\right) \cdot a\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (-.f64 a 1/2) < -5e5

    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. +-commutative99.9%

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

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

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log \left(x + y\right)\right)} \]
      5. fma-def99.8%

        \[\leadsto \left(\log z - t\right) + \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log \left(x + y\right)\right)} \]
      6. sub-neg99.8%

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log \left(x + y\right)\right) \]
      7. metadata-eval99.8%

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log \left(x + y\right)\right) \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in t around inf 99.9%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in a around inf 98.5%

      \[\leadsto \left(\log z - t\right) + \color{blue}{-1 \cdot \left(a \cdot \log \left(\frac{1}{t}\right)\right)} \]
    6. Step-by-step derivation
      1. mul-1-neg98.5%

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-a \cdot \log \left(\frac{1}{t}\right)\right)} \]
      2. log-rec98.5%

        \[\leadsto \left(\log z - t\right) + \left(-a \cdot \color{blue}{\left(-\log t\right)}\right) \]
      3. distribute-rgt-neg-in98.5%

        \[\leadsto \left(\log z - t\right) + \color{blue}{a \cdot \left(-\left(-\log t\right)\right)} \]
      4. remove-double-neg98.5%

        \[\leadsto \left(\log z - t\right) + a \cdot \color{blue}{\log t} \]
    7. Simplified98.5%

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

    if -5e5 < (-.f64 a 1/2) < -0.5

    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. Step-by-step derivation
      1. associate--l+99.6%

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

        \[\leadsto \color{blue}{\left(\left(\log z - t\right) + \log \left(x + y\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      3. associate-+l+99.6%

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

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log \left(x + y\right)\right)} \]
      5. fma-def99.6%

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

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log \left(x + y\right)\right) \]
      7. metadata-eval99.6%

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log \left(x + y\right)\right) \]
    3. Simplified99.6%

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in a around 0 98.1%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(\log \left(y + x\right) + -0.5 \cdot \log t\right)} \]
    5. Step-by-step derivation
      1. +-commutative98.1%

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-0.5 \cdot \log t + \log \left(y + x\right)\right)} \]
    6. Simplified98.1%

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

    if -0.5 < (-.f64 a 1/2)

    1. Initial program 99.8%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.8%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. +-commutative99.8%

        \[\leadsto \color{blue}{\left(\left(\log z - t\right) + \log \left(x + y\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      3. associate-+l+99.8%

        \[\leadsto \color{blue}{\left(\log z - t\right) + \left(\log \left(x + y\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      4. +-commutative99.8%

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log \left(x + y\right)\right)} \]
      5. fma-def99.8%

        \[\leadsto \left(\log z - t\right) + \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log \left(x + y\right)\right)} \]
      6. sub-neg99.8%

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log \left(x + y\right)\right) \]
      7. metadata-eval99.8%

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log \left(x + y\right)\right) \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in t around inf 99.8%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in a around inf 99.1%

      \[\leadsto \left(\log z - t\right) + \color{blue}{-1 \cdot \left(a \cdot \log \left(\frac{1}{t}\right)\right)} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification98.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -500000:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \mathbf{elif}\;a - 0.5 \leq -0.5:\\ \;\;\;\;\left(\log z - t\right) + \left(\log \left(y + x\right) + -0.5 \cdot \log t\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log z - t\right) - \log \left(\frac{1}{t}\right) \cdot a\\ \end{array} \]

Alternative 3: 80.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \log z - t\\ \mathbf{if}\;a - 0.5 \leq -500000:\\ \;\;\;\;t_1 + a \cdot \log t\\ \mathbf{elif}\;a - 0.5 \leq -0.5:\\ \;\;\;\;\left(\log z + \left(\log y + -0.5 \cdot \log t\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;t_1 - \log \left(\frac{1}{t}\right) \cdot a\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (- (log z) t)))
   (if (<= (- a 0.5) -500000.0)
     (+ t_1 (* a (log t)))
     (if (<= (- a 0.5) -0.5)
       (- (+ (log z) (+ (log y) (* -0.5 (log t)))) t)
       (- t_1 (* (log (/ 1.0 t)) a))))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = log(z) - t;
	double tmp;
	if ((a - 0.5) <= -500000.0) {
		tmp = t_1 + (a * log(t));
	} else if ((a - 0.5) <= -0.5) {
		tmp = (log(z) + (log(y) + (-0.5 * log(t)))) - t;
	} else {
		tmp = t_1 - (log((1.0 / t)) * a);
	}
	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 = log(z) - t
    if ((a - 0.5d0) <= (-500000.0d0)) then
        tmp = t_1 + (a * log(t))
    else if ((a - 0.5d0) <= (-0.5d0)) then
        tmp = (log(z) + (log(y) + ((-0.5d0) * log(t)))) - t
    else
        tmp = t_1 - (log((1.0d0 / t)) * a)
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = Math.log(z) - t;
	double tmp;
	if ((a - 0.5) <= -500000.0) {
		tmp = t_1 + (a * Math.log(t));
	} else if ((a - 0.5) <= -0.5) {
		tmp = (Math.log(z) + (Math.log(y) + (-0.5 * Math.log(t)))) - t;
	} else {
		tmp = t_1 - (Math.log((1.0 / t)) * a);
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = math.log(z) - t
	tmp = 0
	if (a - 0.5) <= -500000.0:
		tmp = t_1 + (a * math.log(t))
	elif (a - 0.5) <= -0.5:
		tmp = (math.log(z) + (math.log(y) + (-0.5 * math.log(t)))) - t
	else:
		tmp = t_1 - (math.log((1.0 / t)) * a)
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(log(z) - t)
	tmp = 0.0
	if (Float64(a - 0.5) <= -500000.0)
		tmp = Float64(t_1 + Float64(a * log(t)));
	elseif (Float64(a - 0.5) <= -0.5)
		tmp = Float64(Float64(log(z) + Float64(log(y) + Float64(-0.5 * log(t)))) - t);
	else
		tmp = Float64(t_1 - Float64(log(Float64(1.0 / t)) * a));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = log(z) - t;
	tmp = 0.0;
	if ((a - 0.5) <= -500000.0)
		tmp = t_1 + (a * log(t));
	elseif ((a - 0.5) <= -0.5)
		tmp = (log(z) + (log(y) + (-0.5 * log(t)))) - t;
	else
		tmp = t_1 - (log((1.0 / t)) * a);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision]}, If[LessEqual[N[(a - 0.5), $MachinePrecision], -500000.0], N[(t$95$1 + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[N[(a - 0.5), $MachinePrecision], -0.5], N[(N[(N[Log[z], $MachinePrecision] + N[(N[Log[y], $MachinePrecision] + N[(-0.5 * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(t$95$1 - N[(N[Log[N[(1.0 / t), $MachinePrecision]], $MachinePrecision] * a), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \log z - t\\
\mathbf{if}\;a - 0.5 \leq -500000:\\
\;\;\;\;t_1 + a \cdot \log t\\

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

\mathbf{else}:\\
\;\;\;\;t_1 - \log \left(\frac{1}{t}\right) \cdot a\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (-.f64 a 1/2) < -5e5

    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. +-commutative99.9%

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

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

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log \left(x + y\right)\right)} \]
      5. fma-def99.8%

        \[\leadsto \left(\log z - t\right) + \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log \left(x + y\right)\right)} \]
      6. sub-neg99.8%

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log \left(x + y\right)\right) \]
      7. metadata-eval99.8%

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log \left(x + y\right)\right) \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in t around inf 99.9%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in a around inf 98.5%

      \[\leadsto \left(\log z - t\right) + \color{blue}{-1 \cdot \left(a \cdot \log \left(\frac{1}{t}\right)\right)} \]
    6. Step-by-step derivation
      1. mul-1-neg98.5%

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-a \cdot \log \left(\frac{1}{t}\right)\right)} \]
      2. log-rec98.5%

        \[\leadsto \left(\log z - t\right) + \left(-a \cdot \color{blue}{\left(-\log t\right)}\right) \]
      3. distribute-rgt-neg-in98.5%

        \[\leadsto \left(\log z - t\right) + \color{blue}{a \cdot \left(-\left(-\log t\right)\right)} \]
      4. remove-double-neg98.5%

        \[\leadsto \left(\log z - t\right) + a \cdot \color{blue}{\log t} \]
    7. Simplified98.5%

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

    if -5e5 < (-.f64 a 1/2) < -0.5

    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. Step-by-step derivation
      1. associate--l+99.6%

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

        \[\leadsto \color{blue}{\left(\left(\log z - t\right) + \log \left(x + y\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      3. associate-+l+99.6%

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

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log \left(x + y\right)\right)} \]
      5. fma-def99.6%

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

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log \left(x + y\right)\right) \]
      7. metadata-eval99.6%

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log \left(x + y\right)\right) \]
    3. Simplified99.6%

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in x around 0 61.8%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log y\right)} \]
    5. Taylor expanded in a around 0 60.5%

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

    if -0.5 < (-.f64 a 1/2)

    1. Initial program 99.8%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.8%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. +-commutative99.8%

        \[\leadsto \color{blue}{\left(\left(\log z - t\right) + \log \left(x + y\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      3. associate-+l+99.8%

        \[\leadsto \color{blue}{\left(\log z - t\right) + \left(\log \left(x + y\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      4. +-commutative99.8%

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log \left(x + y\right)\right)} \]
      5. fma-def99.8%

        \[\leadsto \left(\log z - t\right) + \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log \left(x + y\right)\right)} \]
      6. sub-neg99.8%

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log \left(x + y\right)\right) \]
      7. metadata-eval99.8%

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log \left(x + y\right)\right) \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in t around inf 99.8%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in a around inf 99.1%

      \[\leadsto \left(\log z - t\right) + \color{blue}{-1 \cdot \left(a \cdot \log \left(\frac{1}{t}\right)\right)} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification80.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -500000:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \mathbf{elif}\;a - 0.5 \leq -0.5:\\ \;\;\;\;\left(\log z + \left(\log y + -0.5 \cdot \log t\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log z - t\right) - \log \left(\frac{1}{t}\right) \cdot a\\ \end{array} \]

Alternative 4: 99.6% accurate, 1.0× speedup?

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

\\
\left(\left(\log z - t\right) + \log \left(y + x\right)\right) + \left(a + -0.5\right) \cdot \log t
\end{array}
Derivation
  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. sub-neg99.7%

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

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

    \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
  4. Final simplification99.7%

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

Alternative 5: 68.8% accurate, 1.0× speedup?

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

\\
\left(\log z - t\right) + \left(\left(a - 0.5\right) \cdot \log t + \log y\right)
\end{array}
Derivation
  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. +-commutative99.7%

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

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

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

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

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

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

    \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
  4. Taylor expanded in x around 0 72.5%

    \[\leadsto \left(\log z - t\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log y\right)} \]
  5. Final simplification72.5%

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

Alternative 6: 86.1% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 1.5 \cdot 10^{-9}:\\ \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \left(a + -0.5\right) \cdot \log t\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log z - t\right) - \log \left(\frac{1}{t}\right) \cdot a\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 1.5e-9)
   (- (log (* z (+ y x))) (- t (* (+ a -0.5) (log t))))
   (- (- (log z) t) (* (log (/ 1.0 t)) a))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 1.5e-9) {
		tmp = log((z * (y + x))) - (t - ((a + -0.5) * log(t)));
	} else {
		tmp = (log(z) - t) - (log((1.0 / t)) * a);
	}
	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 <= 1.5d-9) then
        tmp = log((z * (y + x))) - (t - ((a + (-0.5d0)) * log(t)))
    else
        tmp = (log(z) - t) - (log((1.0d0 / t)) * a)
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 1.5e-9) {
		tmp = Math.log((z * (y + x))) - (t - ((a + -0.5) * Math.log(t)));
	} else {
		tmp = (Math.log(z) - t) - (Math.log((1.0 / t)) * a);
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 1.5e-9:
		tmp = math.log((z * (y + x))) - (t - ((a + -0.5) * math.log(t)))
	else:
		tmp = (math.log(z) - t) - (math.log((1.0 / t)) * a)
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 1.5e-9)
		tmp = Float64(log(Float64(z * Float64(y + x))) - Float64(t - Float64(Float64(a + -0.5) * log(t))));
	else
		tmp = Float64(Float64(log(z) - t) - Float64(log(Float64(1.0 / t)) * a));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 1.5e-9)
		tmp = log((z * (y + x))) - (t - ((a + -0.5) * log(t)));
	else
		tmp = (log(z) - t) - (log((1.0 / t)) * a);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 1.5e-9], N[(N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - N[(t - N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision] - N[(N[Log[N[(1.0 / t), $MachinePrecision]], $MachinePrecision] * a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 1.5 \cdot 10^{-9}:\\
\;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \left(a + -0.5\right) \cdot \log t\right)\\

\mathbf{else}:\\
\;\;\;\;\left(\log z - t\right) - \log \left(\frac{1}{t}\right) \cdot a\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 1.49999999999999999e-9

    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. Step-by-step derivation
      1. associate--l+99.6%

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

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Step-by-step derivation
      1. metadata-eval99.6%

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

        \[\leadsto \left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \color{blue}{\left(a - 0.5\right)} \cdot \log t \]
      3. associate-+r-99.6%

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \left(a - 0.5\right) \cdot \log t \]
      4. associate-+l-99.6%

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

        \[\leadsto \color{blue}{\left(\log z + \log \left(x + y\right)\right)} - \left(t - \left(a - 0.5\right) \cdot \log t\right) \]
      6. sum-log79.7%

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

        \[\leadsto \log \left(z \cdot \left(x + y\right)\right) - \left(t - \color{blue}{\left(a + \left(-0.5\right)\right)} \cdot \log t\right) \]
      8. metadata-eval79.7%

        \[\leadsto \log \left(z \cdot \left(x + y\right)\right) - \left(t - \left(a + \color{blue}{-0.5}\right) \cdot \log t\right) \]
    5. Applied egg-rr79.7%

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

    if 1.49999999999999999e-9 < 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. +-commutative99.9%

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

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in t around inf 99.9%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in a around inf 98.5%

      \[\leadsto \left(\log z - t\right) + \color{blue}{-1 \cdot \left(a \cdot \log \left(\frac{1}{t}\right)\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification88.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 1.5 \cdot 10^{-9}:\\ \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \left(a + -0.5\right) \cdot \log t\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log z - t\right) - \log \left(\frac{1}{t}\right) \cdot a\\ \end{array} \]

Alternative 7: 86.0% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 9.5 \cdot 10^{-10}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \log \left(z \cdot \left(y + x\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 9.5e-10)
   (+ (* (+ a -0.5) (log t)) (log (* z (+ y x))))
   (+ (- (log z) t) (* a (log t)))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 9.5e-10) {
		tmp = ((a + -0.5) * log(t)) + log((z * (y + x)));
	} else {
		tmp = (log(z) - t) + (a * log(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 <= 9.5d-10) then
        tmp = ((a + (-0.5d0)) * log(t)) + log((z * (y + x)))
    else
        tmp = (log(z) - t) + (a * log(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 <= 9.5e-10) {
		tmp = ((a + -0.5) * Math.log(t)) + Math.log((z * (y + x)));
	} else {
		tmp = (Math.log(z) - t) + (a * Math.log(t));
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 9.5e-10:
		tmp = ((a + -0.5) * math.log(t)) + math.log((z * (y + x)))
	else:
		tmp = (math.log(z) - t) + (a * math.log(t))
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 9.5e-10)
		tmp = Float64(Float64(Float64(a + -0.5) * log(t)) + log(Float64(z * Float64(y + x))));
	else
		tmp = Float64(Float64(log(z) - t) + Float64(a * log(t)));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 9.5e-10)
		tmp = ((a + -0.5) * log(t)) + log((z * (y + x)));
	else
		tmp = (log(z) - t) + (a * log(t));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 9.5e-10], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] + N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 9.5 \cdot 10^{-10}:\\
\;\;\;\;\left(a + -0.5\right) \cdot \log t + \log \left(z \cdot \left(y + x\right)\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 9.50000000000000028e-10

    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. Step-by-step derivation
      1. associate--l+99.6%

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

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Taylor expanded in t around 0 99.3%

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

        \[\leadsto \left(\log z + \log \color{blue}{\left(x + y\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
      2. log-prod79.5%

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

        \[\leadsto \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    6. Simplified79.5%

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

    if 9.50000000000000028e-10 < 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. +-commutative99.9%

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

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in t around inf 99.9%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in a around inf 98.5%

      \[\leadsto \left(\log z - t\right) + \color{blue}{-1 \cdot \left(a \cdot \log \left(\frac{1}{t}\right)\right)} \]
    6. Step-by-step derivation
      1. mul-1-neg98.5%

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-a \cdot \log \left(\frac{1}{t}\right)\right)} \]
      2. log-rec98.5%

        \[\leadsto \left(\log z - t\right) + \left(-a \cdot \color{blue}{\left(-\log t\right)}\right) \]
      3. distribute-rgt-neg-in98.5%

        \[\leadsto \left(\log z - t\right) + \color{blue}{a \cdot \left(-\left(-\log t\right)\right)} \]
      4. remove-double-neg98.5%

        \[\leadsto \left(\log z - t\right) + a \cdot \color{blue}{\log t} \]
    7. Simplified98.5%

      \[\leadsto \left(\log z - t\right) + \color{blue}{a \cdot \log t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification87.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 9.5 \cdot 10^{-10}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \log \left(z \cdot \left(y + x\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \end{array} \]

Alternative 8: 86.1% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 1.1 \cdot 10^{-9}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \log \left(z \cdot \left(y + x\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log z - t\right) - \log \left(\frac{1}{t}\right) \cdot a\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 1.1e-9)
   (+ (* (+ a -0.5) (log t)) (log (* z (+ y x))))
   (- (- (log z) t) (* (log (/ 1.0 t)) a))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 1.1e-9) {
		tmp = ((a + -0.5) * log(t)) + log((z * (y + x)));
	} else {
		tmp = (log(z) - t) - (log((1.0 / t)) * a);
	}
	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 <= 1.1d-9) then
        tmp = ((a + (-0.5d0)) * log(t)) + log((z * (y + x)))
    else
        tmp = (log(z) - t) - (log((1.0d0 / t)) * a)
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 1.1e-9) {
		tmp = ((a + -0.5) * Math.log(t)) + Math.log((z * (y + x)));
	} else {
		tmp = (Math.log(z) - t) - (Math.log((1.0 / t)) * a);
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 1.1e-9:
		tmp = ((a + -0.5) * math.log(t)) + math.log((z * (y + x)))
	else:
		tmp = (math.log(z) - t) - (math.log((1.0 / t)) * a)
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 1.1e-9)
		tmp = Float64(Float64(Float64(a + -0.5) * log(t)) + log(Float64(z * Float64(y + x))));
	else
		tmp = Float64(Float64(log(z) - t) - Float64(log(Float64(1.0 / t)) * a));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 1.1e-9)
		tmp = ((a + -0.5) * log(t)) + log((z * (y + x)));
	else
		tmp = (log(z) - t) - (log((1.0 / t)) * a);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 1.1e-9], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] + N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision] - N[(N[Log[N[(1.0 / t), $MachinePrecision]], $MachinePrecision] * a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 1.1 \cdot 10^{-9}:\\
\;\;\;\;\left(a + -0.5\right) \cdot \log t + \log \left(z \cdot \left(y + x\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\left(\log z - t\right) - \log \left(\frac{1}{t}\right) \cdot a\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 1.0999999999999999e-9

    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. Step-by-step derivation
      1. associate--l+99.6%

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

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Taylor expanded in t around 0 99.3%

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

        \[\leadsto \left(\log z + \log \color{blue}{\left(x + y\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
      2. log-prod79.5%

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

        \[\leadsto \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    6. Simplified79.5%

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

    if 1.0999999999999999e-9 < 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. +-commutative99.9%

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

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in t around inf 99.9%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in a around inf 98.5%

      \[\leadsto \left(\log z - t\right) + \color{blue}{-1 \cdot \left(a \cdot \log \left(\frac{1}{t}\right)\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification87.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 1.1 \cdot 10^{-9}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \log \left(z \cdot \left(y + x\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log z - t\right) - \log \left(\frac{1}{t}\right) \cdot a\\ \end{array} \]

Alternative 9: 73.5% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 1.1 \cdot 10^{-9}:\\ \;\;\;\;\left(a - 0.5\right) \cdot \log t + \log \left(z \cdot y\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 1.1e-9)
   (+ (* (- a 0.5) (log t)) (log (* z y)))
   (+ (- (log z) t) (* a (log t)))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 1.1e-9) {
		tmp = ((a - 0.5) * log(t)) + log((z * y));
	} else {
		tmp = (log(z) - t) + (a * log(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 <= 1.1d-9) then
        tmp = ((a - 0.5d0) * log(t)) + log((z * y))
    else
        tmp = (log(z) - t) + (a * log(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 <= 1.1e-9) {
		tmp = ((a - 0.5) * Math.log(t)) + Math.log((z * y));
	} else {
		tmp = (Math.log(z) - t) + (a * Math.log(t));
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 1.1e-9:
		tmp = ((a - 0.5) * math.log(t)) + math.log((z * y))
	else:
		tmp = (math.log(z) - t) + (a * math.log(t))
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 1.1e-9)
		tmp = Float64(Float64(Float64(a - 0.5) * log(t)) + log(Float64(z * y)));
	else
		tmp = Float64(Float64(log(z) - t) + Float64(a * log(t)));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 1.1e-9)
		tmp = ((a - 0.5) * log(t)) + log((z * y));
	else
		tmp = (log(z) - t) + (a * log(t));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 1.1e-9], N[(N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 1.1 \cdot 10^{-9}:\\
\;\;\;\;\left(a - 0.5\right) \cdot \log t + \log \left(z \cdot y\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 1.0999999999999999e-9

    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. Step-by-step derivation
      1. add-exp-log64.5%

        \[\leadsto \left(\color{blue}{e^{\log \left(\log \left(x + y\right) + \log z\right)}} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. +-commutative64.5%

        \[\leadsto \left(e^{\log \color{blue}{\left(\log z + \log \left(x + y\right)\right)}} - t\right) + \left(a - 0.5\right) \cdot \log t \]
      3. sum-log49.8%

        \[\leadsto \left(e^{\log \color{blue}{\log \left(z \cdot \left(x + y\right)\right)}} - t\right) + \left(a - 0.5\right) \cdot \log t \]
    3. Applied egg-rr49.8%

      \[\leadsto \left(\color{blue}{e^{\log \log \left(z \cdot \left(x + y\right)\right)}} - t\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Taylor expanded in t around 0 79.5%

      \[\leadsto \color{blue}{\left(a - 0.5\right) \cdot \log t + \log \left(\left(y + x\right) \cdot z\right)} \]
    5. Taylor expanded in y around inf 51.6%

      \[\leadsto \left(a - 0.5\right) \cdot \log t + \log \color{blue}{\left(y \cdot z\right)} \]
    6. Step-by-step derivation
      1. *-commutative51.6%

        \[\leadsto \left(a - 0.5\right) \cdot \log t + \log \color{blue}{\left(z \cdot y\right)} \]
    7. Simplified51.6%

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

    if 1.0999999999999999e-9 < 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. +-commutative99.9%

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

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in t around inf 99.9%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in a around inf 98.5%

      \[\leadsto \left(\log z - t\right) + \color{blue}{-1 \cdot \left(a \cdot \log \left(\frac{1}{t}\right)\right)} \]
    6. Step-by-step derivation
      1. mul-1-neg98.5%

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-a \cdot \log \left(\frac{1}{t}\right)\right)} \]
      2. log-rec98.5%

        \[\leadsto \left(\log z - t\right) + \left(-a \cdot \color{blue}{\left(-\log t\right)}\right) \]
      3. distribute-rgt-neg-in98.5%

        \[\leadsto \left(\log z - t\right) + \color{blue}{a \cdot \left(-\left(-\log t\right)\right)} \]
      4. remove-double-neg98.5%

        \[\leadsto \left(\log z - t\right) + a \cdot \color{blue}{\log t} \]
    7. Simplified98.5%

      \[\leadsto \left(\log z - t\right) + \color{blue}{a \cdot \log t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification72.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 1.1 \cdot 10^{-9}:\\ \;\;\;\;\left(a - 0.5\right) \cdot \log t + \log \left(z \cdot y\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \end{array} \]

Alternative 10: 64.1% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 9.2 \cdot 10^{+58}:\\ \;\;\;\;\log z + a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 9.2e+58) (+ (log z) (* a (log t))) (- t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 9.2e+58) {
		tmp = log(z) + (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 (t <= 9.2d+58) then
        tmp = log(z) + (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 (t <= 9.2e+58) {
		tmp = Math.log(z) + (a * Math.log(t));
	} else {
		tmp = -t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 9.2e+58:
		tmp = math.log(z) + (a * math.log(t))
	else:
		tmp = -t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 9.2e+58)
		tmp = Float64(log(z) + 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 (t <= 9.2e+58)
		tmp = log(z) + (a * log(t));
	else
		tmp = -t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 9.2e+58], N[(N[Log[z], $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], (-t)]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 9.2 \cdot 10^{+58}:\\
\;\;\;\;\log z + a \cdot \log t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 9.2000000000000001e58

    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. Step-by-step derivation
      1. associate--l+99.6%

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

        \[\leadsto \color{blue}{\left(\left(\log z - t\right) + \log \left(x + y\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      3. associate-+l+99.6%

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

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log \left(x + y\right)\right)} \]
      5. fma-def99.6%

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

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log \left(x + y\right)\right) \]
      7. metadata-eval99.6%

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log \left(x + y\right)\right) \]
    3. Simplified99.6%

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

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in a around inf 62.7%

      \[\leadsto \left(\log z - t\right) + \color{blue}{-1 \cdot \left(a \cdot \log \left(\frac{1}{t}\right)\right)} \]
    6. Step-by-step derivation
      1. mul-1-neg62.7%

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

        \[\leadsto \left(\log z - t\right) + \left(-a \cdot \color{blue}{\left(-\log t\right)}\right) \]
      3. distribute-rgt-neg-in62.7%

        \[\leadsto \left(\log z - t\right) + \color{blue}{a \cdot \left(-\left(-\log t\right)\right)} \]
      4. remove-double-neg62.7%

        \[\leadsto \left(\log z - t\right) + a \cdot \color{blue}{\log t} \]
    7. Simplified62.7%

      \[\leadsto \left(\log z - t\right) + \color{blue}{a \cdot \log t} \]
    8. Taylor expanded in t around 0 58.8%

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

    if 9.2000000000000001e58 < 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. +-commutative99.9%

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

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in t around inf 100.0%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in t around inf 86.1%

      \[\leadsto \color{blue}{-1 \cdot t} \]
    6. Step-by-step derivation
      1. neg-mul-186.1%

        \[\leadsto \color{blue}{-t} \]
    7. Simplified86.1%

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

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 9.2 \cdot 10^{+58}:\\ \;\;\;\;\log z + a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]

Alternative 11: 56.4% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 9.2 \cdot 10^{+58}:\\ \;\;\;\;\log y + a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 9.2e+58) (+ (log y) (* a (log t))) (- t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 9.2e+58) {
		tmp = log(y) + (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 (t <= 9.2d+58) then
        tmp = log(y) + (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 (t <= 9.2e+58) {
		tmp = Math.log(y) + (a * Math.log(t));
	} else {
		tmp = -t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 9.2e+58:
		tmp = math.log(y) + (a * math.log(t))
	else:
		tmp = -t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 9.2e+58)
		tmp = Float64(log(y) + 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 (t <= 9.2e+58)
		tmp = log(y) + (a * log(t));
	else
		tmp = -t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 9.2e+58], N[(N[Log[y], $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], (-t)]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 9.2 \cdot 10^{+58}:\\
\;\;\;\;\log y + a \cdot \log t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 9.2000000000000001e58

    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. Step-by-step derivation
      1. associate--l+99.6%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.6%

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
    4. Taylor expanded in a around inf 59.9%

      \[\leadsto \log \left(x + y\right) + \color{blue}{a \cdot \log t} \]
    5. Step-by-step derivation
      1. *-commutative59.9%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\log t \cdot a} \]
    6. Simplified59.9%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\log t \cdot a} \]
    7. Taylor expanded in x around 0 49.1%

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

    if 9.2000000000000001e58 < 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. +-commutative99.9%

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

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in t around inf 100.0%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in t around inf 86.1%

      \[\leadsto \color{blue}{-1 \cdot t} \]
    6. Step-by-step derivation
      1. neg-mul-186.1%

        \[\leadsto \color{blue}{-t} \]
    7. Simplified86.1%

      \[\leadsto \color{blue}{-t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification61.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 9.2 \cdot 10^{+58}:\\ \;\;\;\;\log y + a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]

Alternative 12: 76.9% accurate, 1.5× speedup?

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

\\
\left(\log z - t\right) + a \cdot \log t
\end{array}
Derivation
  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. +-commutative99.7%

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

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

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

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

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

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

    \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
  4. Taylor expanded in t around inf 99.7%

    \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
  5. Taylor expanded in a around inf 75.7%

    \[\leadsto \left(\log z - t\right) + \color{blue}{-1 \cdot \left(a \cdot \log \left(\frac{1}{t}\right)\right)} \]
  6. Step-by-step derivation
    1. mul-1-neg75.7%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-a \cdot \log \left(\frac{1}{t}\right)\right)} \]
    2. log-rec75.7%

      \[\leadsto \left(\log z - t\right) + \left(-a \cdot \color{blue}{\left(-\log t\right)}\right) \]
    3. distribute-rgt-neg-in75.7%

      \[\leadsto \left(\log z - t\right) + \color{blue}{a \cdot \left(-\left(-\log t\right)\right)} \]
    4. remove-double-neg75.7%

      \[\leadsto \left(\log z - t\right) + a \cdot \color{blue}{\log t} \]
  7. Simplified75.7%

    \[\leadsto \left(\log z - t\right) + \color{blue}{a \cdot \log t} \]
  8. Final simplification75.7%

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

Alternative 13: 40.9% accurate, 3.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 720:\\ \;\;\;\;\log \left(y + x\right)\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
(FPCore (x y z t a) :precision binary64 (if (<= t 720.0) (log (+ y x)) (- t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 720.0) {
		tmp = log((y + x));
	} 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 <= 720.0d0) then
        tmp = log((y + x))
    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 <= 720.0) {
		tmp = Math.log((y + x));
	} else {
		tmp = -t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 720.0:
		tmp = math.log((y + x))
	else:
		tmp = -t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 720.0)
		tmp = log(Float64(y + x));
	else
		tmp = Float64(-t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 720.0)
		tmp = log((y + x));
	else
		tmp = -t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 720.0], N[Log[N[(y + x), $MachinePrecision]], $MachinePrecision], (-t)]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 720:\\
\;\;\;\;\log \left(y + x\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 720

    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. Step-by-step derivation
      1. associate--l+99.6%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.6%

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

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. fma-def99.6%

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

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

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

        \[\leadsto \log \left(x + y\right) + \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z - t\right) \]
      8. metadata-eval99.6%

        \[\leadsto \log \left(x + y\right) + \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z - t\right) \]
    3. Simplified99.6%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
    4. Taylor expanded in t around inf 8.9%

      \[\leadsto \log \left(x + y\right) + \color{blue}{-1 \cdot t} \]
    5. Step-by-step derivation
      1. neg-mul-18.9%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(-t\right)} \]
    6. Simplified8.9%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(-t\right)} \]
    7. Taylor expanded in t around 0 8.9%

      \[\leadsto \color{blue}{\log \left(y + x\right)} \]

    if 720 < 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. +-commutative99.9%

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

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in t around inf 99.9%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in t around inf 77.1%

      \[\leadsto \color{blue}{-1 \cdot t} \]
    6. Step-by-step derivation
      1. neg-mul-177.1%

        \[\leadsto \color{blue}{-t} \]
    7. Simplified77.1%

      \[\leadsto \color{blue}{-t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification37.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 720:\\ \;\;\;\;\log \left(y + x\right)\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]

Alternative 14: 61.7% accurate, 3.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 1.55 \cdot 10^{+58}:\\ \;\;\;\;a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 1.55e+58) (* a (log t)) (- t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 1.55e+58) {
		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 (t <= 1.55d+58) 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 (t <= 1.55e+58) {
		tmp = a * Math.log(t);
	} else {
		tmp = -t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 1.55e+58:
		tmp = a * math.log(t)
	else:
		tmp = -t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 1.55e+58)
		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 (t <= 1.55e+58)
		tmp = a * log(t);
	else
		tmp = -t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 1.55e+58], N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision], (-t)]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 1.55 \cdot 10^{+58}:\\
\;\;\;\;a \cdot \log t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 1.55e58

    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. Step-by-step derivation
      1. associate--l+99.6%

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

        \[\leadsto \color{blue}{\left(\left(\log z - t\right) + \log \left(x + y\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      3. associate-+l+99.6%

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

        \[\leadsto \left(\log z - t\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log \left(x + y\right)\right)} \]
      5. fma-def99.6%

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

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log \left(x + y\right)\right) \]
      7. metadata-eval99.6%

        \[\leadsto \left(\log z - t\right) + \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log \left(x + y\right)\right) \]
    3. Simplified99.6%

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

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in a around inf 62.7%

      \[\leadsto \left(\log z - t\right) + \color{blue}{-1 \cdot \left(a \cdot \log \left(\frac{1}{t}\right)\right)} \]
    6. Step-by-step derivation
      1. mul-1-neg62.7%

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

        \[\leadsto \left(\log z - t\right) + \left(-a \cdot \color{blue}{\left(-\log t\right)}\right) \]
      3. distribute-rgt-neg-in62.7%

        \[\leadsto \left(\log z - t\right) + \color{blue}{a \cdot \left(-\left(-\log t\right)\right)} \]
      4. remove-double-neg62.7%

        \[\leadsto \left(\log z - t\right) + a \cdot \color{blue}{\log t} \]
    7. Simplified62.7%

      \[\leadsto \left(\log z - t\right) + \color{blue}{a \cdot \log t} \]
    8. Taylor expanded in a around inf 55.1%

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

    if 1.55e58 < 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. +-commutative99.9%

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

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in t around inf 100.0%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
    5. Taylor expanded in t around inf 86.1%

      \[\leadsto \color{blue}{-1 \cdot t} \]
    6. Step-by-step derivation
      1. neg-mul-186.1%

        \[\leadsto \color{blue}{-t} \]
    7. Simplified86.1%

      \[\leadsto \color{blue}{-t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification65.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 1.55 \cdot 10^{+58}:\\ \;\;\;\;a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]

Alternative 15: 37.6% 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 99.7%

    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
  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. +-commutative99.7%

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

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

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

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

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

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

    \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
  4. Taylor expanded in t around inf 99.7%

    \[\leadsto \left(\log z - t\right) + \color{blue}{\left(-1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) + \log \left(y + x\right)\right)} \]
  5. Taylor expanded in t around inf 34.1%

    \[\leadsto \color{blue}{-1 \cdot t} \]
  6. Step-by-step derivation
    1. neg-mul-134.1%

      \[\leadsto \color{blue}{-t} \]
  7. Simplified34.1%

    \[\leadsto \color{blue}{-t} \]
  8. Final simplification34.1%

    \[\leadsto -t \]

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 2023200 
(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))))