Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 20.7s
Alternatives: 14
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 14 alternatives:

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

Initial Program: 99.6% accurate, 1.0× speedup?

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

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

Alternative 1: 99.6% accurate, 0.8× speedup?

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

\\
\mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right) + \log z\right) - t
\end{array}
Derivation
  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. +-commutative99.6%

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

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

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

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

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

    \[\leadsto \color{blue}{\mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right) + \log z\right) - t} \]
  4. Add Preprocessing
  5. Final simplification99.6%

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

Alternative 2: 98.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right)\\ \mathbf{if}\;t \leq 280:\\ \;\;\;\;t_1 + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \left(t_1 - t\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (log (+ x y))))
   (if (<= t 280.0)
     (+ t_1 (+ (log z) (* (log t) (- a 0.5))))
     (+ (* (+ a -0.5) (log t)) (- t_1 t)))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = log((x + y));
	double tmp;
	if (t <= 280.0) {
		tmp = t_1 + (log(z) + (log(t) * (a - 0.5)));
	} else {
		tmp = ((a + -0.5) * log(t)) + (t_1 - t);
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: t_1
    real(8) :: tmp
    t_1 = log((x + y))
    if (t <= 280.0d0) then
        tmp = t_1 + (log(z) + (log(t) * (a - 0.5d0)))
    else
        tmp = ((a + (-0.5d0)) * log(t)) + (t_1 - t)
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = Math.log((x + y));
	double tmp;
	if (t <= 280.0) {
		tmp = t_1 + (Math.log(z) + (Math.log(t) * (a - 0.5)));
	} else {
		tmp = ((a + -0.5) * Math.log(t)) + (t_1 - t);
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = math.log((x + y))
	tmp = 0
	if t <= 280.0:
		tmp = t_1 + (math.log(z) + (math.log(t) * (a - 0.5)))
	else:
		tmp = ((a + -0.5) * math.log(t)) + (t_1 - t)
	return tmp
function code(x, y, z, t, a)
	t_1 = log(Float64(x + y))
	tmp = 0.0
	if (t <= 280.0)
		tmp = Float64(t_1 + Float64(log(z) + Float64(log(t) * Float64(a - 0.5))));
	else
		tmp = Float64(Float64(Float64(a + -0.5) * log(t)) + Float64(t_1 - t));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = log((x + y));
	tmp = 0.0;
	if (t <= 280.0)
		tmp = t_1 + (log(z) + (log(t) * (a - 0.5)));
	else
		tmp = ((a + -0.5) * log(t)) + (t_1 - t);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t, 280.0], N[(t$95$1 + N[(N[Log[z], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] + N[(t$95$1 - t), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \log \left(x + y\right)\\
\mathbf{if}\;t \leq 280:\\
\;\;\;\;t_1 + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\left(a + -0.5\right) \cdot \log t + \left(t_1 - t\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 280

    1. Initial program 99.2%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate-+l-99.2%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right) - \left(t - \left(a - 0.5\right) \cdot \log t\right)} \]
      2. associate--l+99.2%

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

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

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

        \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\left(-\color{blue}{\log t \cdot \left(a - 0.5\right)}\right) + t\right)\right) \]
      6. distribute-rgt-neg-in99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\color{blue}{\log t \cdot \left(-\left(a - 0.5\right)\right)} + t\right)\right) \]
      7. fma-udef99.2%

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

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

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, -\color{blue}{\left(\left(-0.5\right) + a\right)}, t\right)\right) \]
      10. distribute-neg-in99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, \color{blue}{\left(-\left(-0.5\right)\right) + \left(-a\right)}, t\right)\right) \]
      11. metadata-eval99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, \left(-\color{blue}{-0.5}\right) + \left(-a\right), t\right)\right) \]
      12. metadata-eval99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, \color{blue}{0.5} + \left(-a\right), t\right)\right) \]
      13. unsub-neg99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, \color{blue}{0.5 - a}, t\right)\right) \]
    3. Simplified99.2%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in t around 0 98.4%

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

    if 280 < 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. sub-neg99.9%

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. expm1-log1p-u0.0%

        \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\log z - t\right)\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    6. Applied egg-rr0.0%

      \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\log z - t\right)\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    7. Taylor expanded in t around inf 98.8%

      \[\leadsto \left(\log \left(x + y\right) + \color{blue}{-1 \cdot t}\right) + \left(a + -0.5\right) \cdot \log t \]
    8. Step-by-step derivation
      1. neg-mul-198.8%

        \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\left(-t\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    9. Simplified98.8%

      \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\left(-t\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification98.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 280:\\ \;\;\;\;\log \left(x + y\right) + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \left(\log \left(x + y\right) - t\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 81.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 470:\\ \;\;\;\;\log y + \left(\log z - \log t \cdot \left(0.5 - a\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \left(\log \left(x + y\right) - t\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 470.0)
   (+ (log y) (- (log z) (* (log t) (- 0.5 a))))
   (+ (* (+ a -0.5) (log t)) (- (log (+ x y)) t))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 470.0) {
		tmp = log(y) + (log(z) - (log(t) * (0.5 - a)));
	} else {
		tmp = ((a + -0.5) * log(t)) + (log((x + y)) - t);
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 470.0d0) then
        tmp = log(y) + (log(z) - (log(t) * (0.5d0 - a)))
    else
        tmp = ((a + (-0.5d0)) * log(t)) + (log((x + y)) - t)
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 470.0) {
		tmp = Math.log(y) + (Math.log(z) - (Math.log(t) * (0.5 - a)));
	} else {
		tmp = ((a + -0.5) * Math.log(t)) + (Math.log((x + y)) - t);
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 470.0:
		tmp = math.log(y) + (math.log(z) - (math.log(t) * (0.5 - a)))
	else:
		tmp = ((a + -0.5) * math.log(t)) + (math.log((x + y)) - t)
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 470.0)
		tmp = Float64(log(y) + Float64(log(z) - Float64(log(t) * Float64(0.5 - a))));
	else
		tmp = Float64(Float64(Float64(a + -0.5) * log(t)) + Float64(log(Float64(x + y)) - t));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 470.0)
		tmp = log(y) + (log(z) - (log(t) * (0.5 - a)));
	else
		tmp = ((a + -0.5) * log(t)) + (log((x + y)) - t);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 470.0], N[(N[Log[y], $MachinePrecision] + N[(N[Log[z], $MachinePrecision] - N[(N[Log[t], $MachinePrecision] * N[(0.5 - a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] + N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 470:\\
\;\;\;\;\log y + \left(\log z - \log t \cdot \left(0.5 - a\right)\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 470

    1. Initial program 99.2%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.2%

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

        \[\leadsto \left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \color{blue}{\left(a + \left(-0.5\right)\right)} \cdot \log t \]
      3. metadata-eval99.2%

        \[\leadsto \left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + \color{blue}{-0.5}\right) \cdot \log t \]
    3. Simplified99.2%

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 67.3%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
    6. Taylor expanded in t around 0 66.4%

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

    if 470 < 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. sub-neg99.9%

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. expm1-log1p-u0.0%

        \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\log z - t\right)\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    6. Applied egg-rr0.0%

      \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\log z - t\right)\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    7. Taylor expanded in t around inf 98.8%

      \[\leadsto \left(\log \left(x + y\right) + \color{blue}{-1 \cdot t}\right) + \left(a + -0.5\right) \cdot \log t \]
    8. Step-by-step derivation
      1. neg-mul-198.8%

        \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\left(-t\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    9. Simplified98.8%

      \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\left(-t\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification83.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 470:\\ \;\;\;\;\log y + \left(\log z - \log t \cdot \left(0.5 - a\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \left(\log \left(x + y\right) - t\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t \end{array} \]
(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(log(Float64(x + y)) + 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[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision] + N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t
\end{array}
Derivation
  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. Add Preprocessing
  5. Final simplification99.6%

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

Alternative 5: 99.6% accurate, 1.0× speedup?

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

\\
\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \left(a - 0.5\right)
\end{array}
Derivation
  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. Add Preprocessing
  3. Final simplification99.6%

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

Alternative 6: 69.2% accurate, 1.0× speedup?

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

\\
\left(\log y + \left(\log z - \log t \cdot \left(0.5 - a\right)\right)\right) - t
\end{array}
Derivation
  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. Add Preprocessing
  5. Taylor expanded in x around 0 69.2%

    \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
  6. Final simplification69.2%

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

Alternative 7: 87.2% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -3.2 \cdot 10^{+16}:\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{elif}\;a - 0.5 \leq -0.49999998:\\ \;\;\;\;\left(\log \left(\left(x + y\right) \cdot z\right) - t\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \left(\log \left(x + y\right) - t\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= (- a 0.5) -3.2e+16)
   (- (* a (log t)) t)
   (if (<= (- a 0.5) -0.49999998)
     (+ (- (log (* (+ x y) z)) t) (* (log t) (- a 0.5)))
     (+ (* (+ a -0.5) (log t)) (- (log (+ x y)) t)))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a - 0.5) <= -3.2e+16) {
		tmp = (a * log(t)) - t;
	} else if ((a - 0.5) <= -0.49999998) {
		tmp = (log(((x + y) * z)) - t) + (log(t) * (a - 0.5));
	} else {
		tmp = ((a + -0.5) * log(t)) + (log((x + y)) - t);
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if ((a - 0.5d0) <= (-3.2d+16)) then
        tmp = (a * log(t)) - t
    else if ((a - 0.5d0) <= (-0.49999998d0)) then
        tmp = (log(((x + y) * z)) - t) + (log(t) * (a - 0.5d0))
    else
        tmp = ((a + (-0.5d0)) * log(t)) + (log((x + y)) - t)
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a - 0.5) <= -3.2e+16) {
		tmp = (a * Math.log(t)) - t;
	} else if ((a - 0.5) <= -0.49999998) {
		tmp = (Math.log(((x + y) * z)) - t) + (Math.log(t) * (a - 0.5));
	} else {
		tmp = ((a + -0.5) * Math.log(t)) + (Math.log((x + y)) - t);
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if (a - 0.5) <= -3.2e+16:
		tmp = (a * math.log(t)) - t
	elif (a - 0.5) <= -0.49999998:
		tmp = (math.log(((x + y) * z)) - t) + (math.log(t) * (a - 0.5))
	else:
		tmp = ((a + -0.5) * math.log(t)) + (math.log((x + y)) - t)
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (Float64(a - 0.5) <= -3.2e+16)
		tmp = Float64(Float64(a * log(t)) - t);
	elseif (Float64(a - 0.5) <= -0.49999998)
		tmp = Float64(Float64(log(Float64(Float64(x + y) * z)) - t) + Float64(log(t) * Float64(a - 0.5)));
	else
		tmp = Float64(Float64(Float64(a + -0.5) * log(t)) + Float64(log(Float64(x + y)) - t));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if ((a - 0.5) <= -3.2e+16)
		tmp = (a * log(t)) - t;
	elseif ((a - 0.5) <= -0.49999998)
		tmp = (log(((x + y) * z)) - t) + (log(t) * (a - 0.5));
	else
		tmp = ((a + -0.5) * log(t)) + (log((x + y)) - t);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[N[(a - 0.5), $MachinePrecision], -3.2e+16], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[N[(a - 0.5), $MachinePrecision], -0.49999998], N[(N[(N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] + N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a - 0.5 \leq -3.2 \cdot 10^{+16}:\\
\;\;\;\;a \cdot \log t - t\\

\mathbf{elif}\;a - 0.5 \leq -0.49999998:\\
\;\;\;\;\left(\log \left(\left(x + y\right) \cdot z\right) - t\right) + \log t \cdot \left(a - 0.5\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (-.f64 a 1/2) < -3.2e16

    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. sub-neg99.8%

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 69.8%

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

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    7. Step-by-step derivation
      1. *-commutative99.8%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    8. Simplified99.8%

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

    if -3.2e16 < (-.f64 a 1/2) < -0.49999998000000001

    1. Initial program 99.5%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. sum-log77.9%

        \[\leadsto \left(\color{blue}{\log \left(\left(x + y\right) \cdot z\right)} - t\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Applied egg-rr77.9%

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

    if -0.49999998000000001 < (-.f64 a 1/2)

    1. Initial program 99.5%

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

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

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. expm1-log1p-u24.4%

        \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\log z - t\right)\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    6. Applied egg-rr24.4%

      \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\log z - t\right)\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    7. Taylor expanded in t around inf 99.5%

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

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

      \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\left(-t\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
  3. Recombined 3 regimes into one program.
  4. Final simplification88.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -3.2 \cdot 10^{+16}:\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{elif}\;a - 0.5 \leq -0.49999998:\\ \;\;\;\;\left(\log \left(\left(x + y\right) \cdot z\right) - t\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \left(\log \left(x + y\right) - t\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 79.1% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -4.6 \lor \neg \left(a \leq 2.3 \cdot 10^{-8}\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + y\right) + \left(\log z - t\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (or (<= a -4.6) (not (<= a 2.3e-8)))
   (- (* a (log t)) t)
   (+ (log (+ x y)) (- (log z) t))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a <= -4.6) || !(a <= 2.3e-8)) {
		tmp = (a * log(t)) - t;
	} else {
		tmp = log((x + y)) + (log(z) - t);
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if ((a <= (-4.6d0)) .or. (.not. (a <= 2.3d-8))) then
        tmp = (a * log(t)) - t
    else
        tmp = log((x + y)) + (log(z) - t)
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a <= -4.6) || !(a <= 2.3e-8)) {
		tmp = (a * Math.log(t)) - t;
	} else {
		tmp = Math.log((x + y)) + (Math.log(z) - t);
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if (a <= -4.6) or not (a <= 2.3e-8):
		tmp = (a * math.log(t)) - t
	else:
		tmp = math.log((x + y)) + (math.log(z) - t)
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if ((a <= -4.6) || !(a <= 2.3e-8))
		tmp = Float64(Float64(a * log(t)) - t);
	else
		tmp = Float64(log(Float64(x + y)) + Float64(log(z) - t));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if ((a <= -4.6) || ~((a <= 2.3e-8)))
		tmp = (a * log(t)) - t;
	else
		tmp = log((x + y)) + (log(z) - t);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[Or[LessEqual[a, -4.6], N[Not[LessEqual[a, 2.3e-8]], $MachinePrecision]], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -4.6 \lor \neg \left(a \leq 2.3 \cdot 10^{-8}\right):\\
\;\;\;\;a \cdot \log t - t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -4.5999999999999996 or 2.3000000000000001e-8 < a

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. 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. Add Preprocessing
    5. Taylor expanded in x around 0 74.0%

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

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

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    8. Simplified99.1%

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

    if -4.5999999999999996 < a < 2.3000000000000001e-8

    1. Initial program 99.5%

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

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

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

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

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

        \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\left(-\color{blue}{\log t \cdot \left(a - 0.5\right)}\right) + t\right)\right) \]
      6. distribute-rgt-neg-in99.5%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\color{blue}{\log t \cdot \left(-\left(a - 0.5\right)\right)} + t\right)\right) \]
      7. fma-udef99.5%

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

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

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, -\color{blue}{\left(\left(-0.5\right) + a\right)}, t\right)\right) \]
      10. distribute-neg-in99.5%

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in t around inf 60.6%

      \[\leadsto \log \left(x + y\right) + \left(\log z - \color{blue}{t}\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification79.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -4.6 \lor \neg \left(a \leq 2.3 \cdot 10^{-8}\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + y\right) + \left(\log z - t\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 9: 87.6% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 1.8 \cdot 10^{-7}:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 1.8e-7)
   (+ (log (* (+ x y) z)) (* (log t) (- a 0.5)))
   (- (* a (log t)) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 1.8e-7) {
		tmp = log(((x + y) * z)) + (log(t) * (a - 0.5));
	} else {
		tmp = (a * log(t)) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 1.8d-7) then
        tmp = log(((x + y) * z)) + (log(t) * (a - 0.5d0))
    else
        tmp = (a * log(t)) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 1.8e-7) {
		tmp = Math.log(((x + y) * z)) + (Math.log(t) * (a - 0.5));
	} else {
		tmp = (a * Math.log(t)) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 1.8e-7:
		tmp = math.log(((x + y) * z)) + (math.log(t) * (a - 0.5))
	else:
		tmp = (a * math.log(t)) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 1.8e-7)
		tmp = Float64(log(Float64(Float64(x + y) * z)) + Float64(log(t) * Float64(a - 0.5)));
	else
		tmp = Float64(Float64(a * log(t)) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 1.8e-7)
		tmp = log(((x + y) * z)) + (log(t) * (a - 0.5));
	else
		tmp = (a * log(t)) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 1.8e-7], N[(N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 1.8 \cdot 10^{-7}:\\
\;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 1.79999999999999997e-7

    1. Initial program 99.3%

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

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right) - \left(t - \left(a - 0.5\right) \cdot \log t\right)} \]
      2. associate--l+99.2%

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

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

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

        \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\left(-\color{blue}{\log t \cdot \left(a - 0.5\right)}\right) + t\right)\right) \]
      6. distribute-rgt-neg-in99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\color{blue}{\log t \cdot \left(-\left(a - 0.5\right)\right)} + t\right)\right) \]
      7. fma-udef99.2%

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

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

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, -\color{blue}{\left(\left(-0.5\right) + a\right)}, t\right)\right) \]
      10. distribute-neg-in99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, \color{blue}{\left(-\left(-0.5\right)\right) + \left(-a\right)}, t\right)\right) \]
      11. metadata-eval99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, \left(-\color{blue}{-0.5}\right) + \left(-a\right), t\right)\right) \]
      12. metadata-eval99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, \color{blue}{0.5} + \left(-a\right), t\right)\right) \]
      13. unsub-neg99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, \color{blue}{0.5 - a}, t\right)\right) \]
    3. Simplified99.2%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in t around 0 99.2%

      \[\leadsto \color{blue}{\left(\log z + \log \left(x + y\right)\right) - \log t \cdot \left(0.5 - a\right)} \]
    6. Step-by-step derivation
      1. log-prod71.1%

        \[\leadsto \color{blue}{\log \left(z \cdot \left(x + y\right)\right)} - \log t \cdot \left(0.5 - a\right) \]
      2. +-commutative71.1%

        \[\leadsto \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - \log t \cdot \left(0.5 - a\right) \]
    7. Simplified71.1%

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

    if 1.79999999999999997e-7 < t

    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. sub-neg99.8%

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 71.9%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
    6. Taylor expanded in a around inf 97.5%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    7. Step-by-step derivation
      1. *-commutative97.5%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    8. Simplified97.5%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification85.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 1.8 \cdot 10^{-7}:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \]
  5. Add Preprocessing

Alternative 10: 87.7% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 2.15 \cdot 10^{-7}:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \left(\log \left(x + y\right) - t\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 2.15e-7)
   (+ (log (* (+ x y) z)) (* (log t) (- a 0.5)))
   (+ (* (+ a -0.5) (log t)) (- (log (+ x y)) t))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 2.15e-7) {
		tmp = log(((x + y) * z)) + (log(t) * (a - 0.5));
	} else {
		tmp = ((a + -0.5) * log(t)) + (log((x + y)) - t);
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 2.15d-7) then
        tmp = log(((x + y) * z)) + (log(t) * (a - 0.5d0))
    else
        tmp = ((a + (-0.5d0)) * log(t)) + (log((x + y)) - t)
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 2.15e-7) {
		tmp = Math.log(((x + y) * z)) + (Math.log(t) * (a - 0.5));
	} else {
		tmp = ((a + -0.5) * Math.log(t)) + (Math.log((x + y)) - t);
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 2.15e-7:
		tmp = math.log(((x + y) * z)) + (math.log(t) * (a - 0.5))
	else:
		tmp = ((a + -0.5) * math.log(t)) + (math.log((x + y)) - t)
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 2.15e-7)
		tmp = Float64(log(Float64(Float64(x + y) * z)) + Float64(log(t) * Float64(a - 0.5)));
	else
		tmp = Float64(Float64(Float64(a + -0.5) * log(t)) + Float64(log(Float64(x + y)) - t));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 2.15e-7)
		tmp = log(((x + y) * z)) + (log(t) * (a - 0.5));
	else
		tmp = ((a + -0.5) * log(t)) + (log((x + y)) - t);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 2.15e-7], N[(N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] + N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 2.15 \cdot 10^{-7}:\\
\;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 2.1500000000000001e-7

    1. Initial program 99.3%

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

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right) - \left(t - \left(a - 0.5\right) \cdot \log t\right)} \]
      2. associate--l+99.2%

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

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

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

        \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\left(-\color{blue}{\log t \cdot \left(a - 0.5\right)}\right) + t\right)\right) \]
      6. distribute-rgt-neg-in99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\color{blue}{\log t \cdot \left(-\left(a - 0.5\right)\right)} + t\right)\right) \]
      7. fma-udef99.2%

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

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

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, -\color{blue}{\left(\left(-0.5\right) + a\right)}, t\right)\right) \]
      10. distribute-neg-in99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, \color{blue}{\left(-\left(-0.5\right)\right) + \left(-a\right)}, t\right)\right) \]
      11. metadata-eval99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, \left(-\color{blue}{-0.5}\right) + \left(-a\right), t\right)\right) \]
      12. metadata-eval99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, \color{blue}{0.5} + \left(-a\right), t\right)\right) \]
      13. unsub-neg99.2%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, \color{blue}{0.5 - a}, t\right)\right) \]
    3. Simplified99.2%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in t around 0 99.2%

      \[\leadsto \color{blue}{\left(\log z + \log \left(x + y\right)\right) - \log t \cdot \left(0.5 - a\right)} \]
    6. Step-by-step derivation
      1. log-prod71.1%

        \[\leadsto \color{blue}{\log \left(z \cdot \left(x + y\right)\right)} - \log t \cdot \left(0.5 - a\right) \]
      2. +-commutative71.1%

        \[\leadsto \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - \log t \cdot \left(0.5 - a\right) \]
    7. Simplified71.1%

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

    if 2.1500000000000001e-7 < t

    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. sub-neg99.8%

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. expm1-log1p-u2.7%

        \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\log z - t\right)\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    6. Applied egg-rr2.7%

      \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\log z - t\right)\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    7. Taylor expanded in t around inf 97.6%

      \[\leadsto \left(\log \left(x + y\right) + \color{blue}{-1 \cdot t}\right) + \left(a + -0.5\right) \cdot \log t \]
    8. Step-by-step derivation
      1. neg-mul-197.6%

        \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\left(-t\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
    9. Simplified97.6%

      \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\left(-t\right)}\right) + \left(a + -0.5\right) \cdot \log t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification85.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 2.15 \cdot 10^{-7}:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \left(\log \left(x + y\right) - t\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 11: 74.2% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 2.35 \cdot 10^{-8}:\\ \;\;\;\;\log \left(y \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 2.35e-8)
   (+ (log (* y z)) (* (log t) (- a 0.5)))
   (- (* a (log t)) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 2.35e-8) {
		tmp = log((y * z)) + (log(t) * (a - 0.5));
	} else {
		tmp = (a * log(t)) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 2.35d-8) then
        tmp = log((y * z)) + (log(t) * (a - 0.5d0))
    else
        tmp = (a * log(t)) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 2.35e-8) {
		tmp = Math.log((y * z)) + (Math.log(t) * (a - 0.5));
	} else {
		tmp = (a * Math.log(t)) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 2.35e-8:
		tmp = math.log((y * z)) + (math.log(t) * (a - 0.5))
	else:
		tmp = (a * math.log(t)) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 2.35e-8)
		tmp = Float64(log(Float64(y * z)) + Float64(log(t) * Float64(a - 0.5)));
	else
		tmp = Float64(Float64(a * log(t)) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 2.35e-8)
		tmp = log((y * z)) + (log(t) * (a - 0.5));
	else
		tmp = (a * log(t)) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 2.35e-8], N[(N[Log[N[(y * z), $MachinePrecision]], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 2.35 \cdot 10^{-8}:\\
\;\;\;\;\log \left(y \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 2.3499999999999999e-8

    1. Initial program 99.3%

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

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

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 65.8%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
    6. Taylor expanded in t around 0 65.8%

      \[\leadsto \color{blue}{\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)} \]
    7. Taylor expanded in t around inf 65.8%

      \[\leadsto \color{blue}{\log y + \left(\log z + -1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right)\right)} \]
    8. Step-by-step derivation
      1. associate-+r+65.9%

        \[\leadsto \color{blue}{\left(\log y + \log z\right) + -1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right)} \]
      2. log-prod49.5%

        \[\leadsto \color{blue}{\log \left(y \cdot z\right)} + -1 \cdot \left(\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right) \]
      3. mul-1-neg49.5%

        \[\leadsto \log \left(y \cdot z\right) + \color{blue}{\left(-\log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)\right)} \]
      4. unsub-neg49.5%

        \[\leadsto \color{blue}{\log \left(y \cdot z\right) - \log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right)} \]
      5. *-commutative49.5%

        \[\leadsto \log \color{blue}{\left(z \cdot y\right)} - \log \left(\frac{1}{t}\right) \cdot \left(a - 0.5\right) \]
      6. log-rec49.5%

        \[\leadsto \log \left(z \cdot y\right) - \color{blue}{\left(-\log t\right)} \cdot \left(a - 0.5\right) \]
      7. sub-neg49.5%

        \[\leadsto \log \left(z \cdot y\right) - \left(-\log t\right) \cdot \color{blue}{\left(a + \left(-0.5\right)\right)} \]
      8. metadata-eval49.5%

        \[\leadsto \log \left(z \cdot y\right) - \left(-\log t\right) \cdot \left(a + \color{blue}{-0.5}\right) \]
    9. Simplified49.5%

      \[\leadsto \color{blue}{\log \left(z \cdot y\right) - \left(-\log t\right) \cdot \left(a + -0.5\right)} \]
    10. Taylor expanded in t around 0 49.5%

      \[\leadsto \log \left(z \cdot y\right) - \color{blue}{-1 \cdot \left(\log t \cdot \left(a - 0.5\right)\right)} \]
    11. Step-by-step derivation
      1. mul-1-neg49.5%

        \[\leadsto \log \left(z \cdot y\right) - \color{blue}{\left(-\log t \cdot \left(a - 0.5\right)\right)} \]
      2. sub-neg49.5%

        \[\leadsto \log \left(z \cdot y\right) - \left(-\log t \cdot \color{blue}{\left(a + \left(-0.5\right)\right)}\right) \]
      3. metadata-eval49.5%

        \[\leadsto \log \left(z \cdot y\right) - \left(-\log t \cdot \left(a + \color{blue}{-0.5}\right)\right) \]
      4. distribute-rgt-neg-in49.5%

        \[\leadsto \log \left(z \cdot y\right) - \color{blue}{\log t \cdot \left(-\left(a + -0.5\right)\right)} \]
      5. neg-sub049.5%

        \[\leadsto \log \left(z \cdot y\right) - \log t \cdot \color{blue}{\left(0 - \left(a + -0.5\right)\right)} \]
      6. +-commutative49.5%

        \[\leadsto \log \left(z \cdot y\right) - \log t \cdot \left(0 - \color{blue}{\left(-0.5 + a\right)}\right) \]
      7. associate--r+49.5%

        \[\leadsto \log \left(z \cdot y\right) - \log t \cdot \color{blue}{\left(\left(0 - -0.5\right) - a\right)} \]
      8. metadata-eval49.5%

        \[\leadsto \log \left(z \cdot y\right) - \log t \cdot \left(\color{blue}{0.5} - a\right) \]
    12. Simplified49.5%

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

    if 2.3499999999999999e-8 < t

    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. sub-neg99.8%

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 71.9%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
    6. Taylor expanded in a around inf 97.5%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    7. Step-by-step derivation
      1. *-commutative97.5%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    8. Simplified97.5%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification76.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 2.35 \cdot 10^{-8}:\\ \;\;\;\;\log \left(y \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \]
  5. Add Preprocessing

Alternative 12: 61.2% accurate, 2.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 1.72 \cdot 10^{+86}:\\ \;\;\;\;a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 1.72e+86) (* a (log t)) (- t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 1.72e+86) {
		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 <= 1.72d+86) 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 <= 1.72e+86) {
		tmp = a * Math.log(t);
	} else {
		tmp = -t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 1.72e+86:
		tmp = a * math.log(t)
	else:
		tmp = -t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 1.72e+86)
		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 <= 1.72e+86)
		tmp = a * log(t);
	else
		tmp = -t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 1.72e+86], N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision], (-t)]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 1.72 \cdot 10^{+86}:\\
\;\;\;\;a \cdot \log t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 1.72e86

    1. Initial program 99.3%

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

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

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

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

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

        \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\left(-\color{blue}{\log t \cdot \left(a - 0.5\right)}\right) + t\right)\right) \]
      6. distribute-rgt-neg-in99.3%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\color{blue}{\log t \cdot \left(-\left(a - 0.5\right)\right)} + t\right)\right) \]
      7. fma-udef99.3%

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

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

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, -\color{blue}{\left(\left(-0.5\right) + a\right)}, t\right)\right) \]
      10. distribute-neg-in99.3%

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in a around inf 51.1%

      \[\leadsto \color{blue}{a \cdot \log t} \]
    6. Step-by-step derivation
      1. *-commutative51.1%

        \[\leadsto \color{blue}{\log t \cdot a} \]
    7. Simplified51.1%

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

    if 1.72e86 < 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%

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

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

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

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

        \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\left(-\color{blue}{\log t \cdot \left(a - 0.5\right)}\right) + t\right)\right) \]
      6. distribute-rgt-neg-in99.9%

        \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\color{blue}{\log t \cdot \left(-\left(a - 0.5\right)\right)} + t\right)\right) \]
      7. fma-udef99.9%

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

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

        \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, -\color{blue}{\left(\left(-0.5\right) + a\right)}, t\right)\right) \]
      10. distribute-neg-in99.9%

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in t around inf 81.5%

      \[\leadsto \color{blue}{-1 \cdot t} \]
    6. Step-by-step derivation
      1. neg-mul-181.5%

        \[\leadsto \color{blue}{-t} \]
    7. Simplified81.5%

      \[\leadsto \color{blue}{-t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification64.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 1.72 \cdot 10^{+86}:\\ \;\;\;\;a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]
  5. Add Preprocessing

Alternative 13: 75.4% accurate, 3.0× speedup?

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

\\
a \cdot \log t - t
\end{array}
Derivation
  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. Add Preprocessing
  5. Taylor expanded in x around 0 69.2%

    \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
  6. Taylor expanded in a around inf 76.1%

    \[\leadsto \color{blue}{a \cdot \log t} - t \]
  7. Step-by-step derivation
    1. *-commutative76.1%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  8. Simplified76.1%

    \[\leadsto \color{blue}{\log t \cdot a} - t \]
  9. Final simplification76.1%

    \[\leadsto a \cdot \log t - t \]
  10. Add Preprocessing

Alternative 14: 38.2% 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 99.6%

    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
  2. Step-by-step derivation
    1. associate-+l-99.6%

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

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

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

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

      \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\left(-\color{blue}{\log t \cdot \left(a - 0.5\right)}\right) + t\right)\right) \]
    6. distribute-rgt-neg-in99.6%

      \[\leadsto \log \left(x + y\right) + \left(\log z - \left(\color{blue}{\log t \cdot \left(-\left(a - 0.5\right)\right)} + t\right)\right) \]
    7. fma-udef99.6%

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

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

      \[\leadsto \log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, -\color{blue}{\left(\left(-0.5\right) + a\right)}, t\right)\right) \]
    10. distribute-neg-in99.6%

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

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

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

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

    \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\log z - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in t around inf 40.3%

    \[\leadsto \color{blue}{-1 \cdot t} \]
  6. Step-by-step derivation
    1. neg-mul-140.3%

      \[\leadsto \color{blue}{-t} \]
  7. Simplified40.3%

    \[\leadsto \color{blue}{-t} \]
  8. Final simplification40.3%

    \[\leadsto -t \]
  9. Add Preprocessing

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 2024024 
(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))))