Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 15.3s
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?

\[\begin{array}{l} \\ \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \left(a - 0.5\right) \end{array} \]
(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. Final simplification99.6%

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

Alternative 2: 85.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\log z \leq 230:\\ \;\;\;\;\left(\log \left(\left(x + y\right) \cdot z\right) + \log t \cdot \left(a - 0.5\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= (log z) 230.0)
   (- (+ (log (* (+ x y) z)) (* (log t) (- a 0.5))) t)
   (- (* a (log t)) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (log(z) <= 230.0) {
		tmp = (log(((x + y) * z)) + (log(t) * (a - 0.5))) - t;
	} else {
		tmp = (a * log(t)) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (log(z) <= 230.0d0) then
        tmp = (log(((x + y) * z)) + (log(t) * (a - 0.5d0))) - t
    else
        tmp = (a * log(t)) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (Math.log(z) <= 230.0) {
		tmp = (Math.log(((x + y) * z)) + (Math.log(t) * (a - 0.5))) - t;
	} else {
		tmp = (a * Math.log(t)) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if math.log(z) <= 230.0:
		tmp = (math.log(((x + y) * z)) + (math.log(t) * (a - 0.5))) - t
	else:
		tmp = (a * math.log(t)) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (log(z) <= 230.0)
		tmp = Float64(Float64(log(Float64(Float64(x + y) * z)) + Float64(log(t) * Float64(a - 0.5))) - t);
	else
		tmp = Float64(Float64(a * log(t)) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (log(z) <= 230.0)
		tmp = (log(((x + y) * z)) + (log(t) * (a - 0.5))) - t;
	else
		tmp = (a * log(t)) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[N[Log[z], $MachinePrecision], 230.0], N[(N[(N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\log z \leq 230:\\
\;\;\;\;\left(\log \left(\left(x + y\right) \cdot z\right) + \log t \cdot \left(a - 0.5\right)\right) - t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (log.f64 z) < 230

    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%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log z + \left(\log \left(x + y\right) - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
    4. Step-by-step derivation
      1. associate-+r-99.7%

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

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

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

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

        \[\leadsto \left(\color{blue}{\left(\log z + \log \left(x + y\right)\right)} - \log t \cdot \left(0.5 - a\right)\right) - t \]
      6. sum-log96.2%

        \[\leadsto \left(\color{blue}{\log \left(z \cdot \left(x + y\right)\right)} - \log t \cdot \left(0.5 - a\right)\right) - t \]
    5. Applied egg-rr96.2%

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

    if 230 < (log.f64 z)

    1. Initial program 99.6%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 63.0%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \left(\log t \cdot \left(a - 0.5\right) + \frac{x}{y}\right)\right)\right) - t} \]
    3. Taylor expanded in a around inf 80.5%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    4. Step-by-step derivation
      1. *-commutative80.5%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    5. Simplified80.5%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification90.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\log z \leq 230:\\ \;\;\;\;\left(\log \left(\left(x + y\right) \cdot z\right) + \log t \cdot \left(a - 0.5\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \]

Alternative 3: 76.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -1450000000 \lor \neg \left(a \leq 0.64\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log z + \log \left(y \cdot \sqrt{\frac{1}{t}}\right)\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (or (<= a -1450000000.0) (not (<= a 0.64)))
   (- (* a (log t)) t)
   (- (+ (log z) (log (* y (sqrt (/ 1.0 t))))) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a <= -1450000000.0) || !(a <= 0.64)) {
		tmp = (a * log(t)) - t;
	} else {
		tmp = (log(z) + log((y * sqrt((1.0 / 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 ((a <= (-1450000000.0d0)) .or. (.not. (a <= 0.64d0))) then
        tmp = (a * log(t)) - t
    else
        tmp = (log(z) + log((y * sqrt((1.0d0 / 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 ((a <= -1450000000.0) || !(a <= 0.64)) {
		tmp = (a * Math.log(t)) - t;
	} else {
		tmp = (Math.log(z) + Math.log((y * Math.sqrt((1.0 / t))))) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if (a <= -1450000000.0) or not (a <= 0.64):
		tmp = (a * math.log(t)) - t
	else:
		tmp = (math.log(z) + math.log((y * math.sqrt((1.0 / t))))) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if ((a <= -1450000000.0) || !(a <= 0.64))
		tmp = Float64(Float64(a * log(t)) - t);
	else
		tmp = Float64(Float64(log(z) + log(Float64(y * sqrt(Float64(1.0 / t))))) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if ((a <= -1450000000.0) || ~((a <= 0.64)))
		tmp = (a * log(t)) - t;
	else
		tmp = (log(z) + log((y * sqrt((1.0 / t))))) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[Or[LessEqual[a, -1450000000.0], N[Not[LessEqual[a, 0.64]], $MachinePrecision]], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(N[Log[z], $MachinePrecision] + N[Log[N[(y * N[Sqrt[N[(1.0 / t), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -1450000000 \lor \neg \left(a \leq 0.64\right):\\
\;\;\;\;a \cdot \log t - t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -1.45e9 or 0.640000000000000013 < a

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 63.9%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \left(\log t \cdot \left(a - 0.5\right) + \frac{x}{y}\right)\right)\right) - t} \]
    3. Taylor expanded in a around inf 98.7%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    4. Step-by-step derivation
      1. *-commutative98.7%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    5. Simplified98.7%

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

    if -1.45e9 < a < 0.640000000000000013

    1. Initial program 99.5%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in a around 0 97.6%

      \[\leadsto \color{blue}{\left(\log z + \left(\log \left(x + y\right) + -0.5 \cdot \log t\right)\right) - t} \]
    3. Step-by-step derivation
      1. associate-+r+97.7%

        \[\leadsto \color{blue}{\left(\left(\log z + \log \left(x + y\right)\right) + -0.5 \cdot \log t\right)} - t \]
      2. log-prod77.3%

        \[\leadsto \left(\color{blue}{\log \left(z \cdot \left(x + y\right)\right)} + -0.5 \cdot \log t\right) - t \]
      3. add-log-exp77.3%

        \[\leadsto \left(\log \left(z \cdot \left(x + y\right)\right) + \color{blue}{\log \left(e^{-0.5 \cdot \log t}\right)}\right) - t \]
      4. sum-log69.4%

        \[\leadsto \color{blue}{\log \left(\left(z \cdot \left(x + y\right)\right) \cdot e^{-0.5 \cdot \log t}\right)} - t \]
      5. +-commutative69.4%

        \[\leadsto \log \left(\left(z \cdot \color{blue}{\left(y + x\right)}\right) \cdot e^{-0.5 \cdot \log t}\right) - t \]
      6. *-commutative69.4%

        \[\leadsto \log \left(\left(z \cdot \left(y + x\right)\right) \cdot e^{\color{blue}{\log t \cdot -0.5}}\right) - t \]
      7. exp-to-pow69.5%

        \[\leadsto \log \left(\left(z \cdot \left(y + x\right)\right) \cdot \color{blue}{{t}^{-0.5}}\right) - t \]
    4. Applied egg-rr69.5%

      \[\leadsto \color{blue}{\log \left(\left(z \cdot \left(y + x\right)\right) \cdot {t}^{-0.5}\right)} - t \]
    5. Taylor expanded in y around inf 46.0%

      \[\leadsto \log \left(\color{blue}{\left(y \cdot z\right)} \cdot {t}^{-0.5}\right) - t \]
    6. Taylor expanded in z around 0 59.0%

      \[\leadsto \color{blue}{\left(\log z + \log \left(\sqrt{\frac{1}{t}} \cdot y\right)\right)} - t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification80.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -1450000000 \lor \neg \left(a \leq 0.64\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log z + \log \left(y \cdot \sqrt{\frac{1}{t}}\right)\right) - t\\ \end{array} \]

Alternative 4: 80.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -1450000000 \lor \neg \left(a \leq 2.2\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log z + \left(\log y + \log t \cdot -0.5\right)\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (or (<= a -1450000000.0) (not (<= a 2.2)))
   (- (* a (log t)) t)
   (- (+ (log z) (+ (log y) (* (log t) -0.5))) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a <= -1450000000.0) || !(a <= 2.2)) {
		tmp = (a * log(t)) - t;
	} else {
		tmp = (log(z) + (log(y) + (log(t) * -0.5))) - 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 <= (-1450000000.0d0)) .or. (.not. (a <= 2.2d0))) then
        tmp = (a * log(t)) - t
    else
        tmp = (log(z) + (log(y) + (log(t) * (-0.5d0)))) - 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 <= -1450000000.0) || !(a <= 2.2)) {
		tmp = (a * Math.log(t)) - t;
	} else {
		tmp = (Math.log(z) + (Math.log(y) + (Math.log(t) * -0.5))) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if (a <= -1450000000.0) or not (a <= 2.2):
		tmp = (a * math.log(t)) - t
	else:
		tmp = (math.log(z) + (math.log(y) + (math.log(t) * -0.5))) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if ((a <= -1450000000.0) || !(a <= 2.2))
		tmp = Float64(Float64(a * log(t)) - t);
	else
		tmp = Float64(Float64(log(z) + Float64(log(y) + Float64(log(t) * -0.5))) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if ((a <= -1450000000.0) || ~((a <= 2.2)))
		tmp = (a * log(t)) - t;
	else
		tmp = (log(z) + (log(y) + (log(t) * -0.5))) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[Or[LessEqual[a, -1450000000.0], N[Not[LessEqual[a, 2.2]], $MachinePrecision]], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(N[Log[z], $MachinePrecision] + N[(N[Log[y], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -1450000000 \lor \neg \left(a \leq 2.2\right):\\
\;\;\;\;a \cdot \log t - t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -1.45e9 or 2.2000000000000002 < a

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 63.9%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \left(\log t \cdot \left(a - 0.5\right) + \frac{x}{y}\right)\right)\right) - t} \]
    3. Taylor expanded in a around inf 98.7%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    4. Step-by-step derivation
      1. *-commutative98.7%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    5. Simplified98.7%

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

    if -1.45e9 < a < 2.2000000000000002

    1. Initial program 99.5%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in a around 0 97.6%

      \[\leadsto \color{blue}{\left(\log z + \left(\log \left(x + y\right) + -0.5 \cdot \log t\right)\right) - t} \]
    3. Taylor expanded in x around 0 66.0%

      \[\leadsto \left(\log z + \color{blue}{\left(\log y + -0.5 \cdot \log t\right)}\right) - t \]
    4. Step-by-step derivation
      1. *-commutative66.0%

        \[\leadsto \left(\log z + \left(\log y + \color{blue}{\log t \cdot -0.5}\right)\right) - t \]
    5. Simplified66.0%

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

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -1450000000 \lor \neg \left(a \leq 2.2\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log z + \left(\log y + \log t \cdot -0.5\right)\right) - t\\ \end{array} \]

Alternative 5: 64.3% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\log z \leq 230:\\ \;\;\;\;\left(\log \left(y \cdot z\right) + \log t \cdot \left(a - 0.5\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= (log z) 230.0)
   (- (+ (log (* y z)) (* (log t) (- a 0.5))) t)
   (- (* a (log t)) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (log(z) <= 230.0) {
		tmp = (log((y * z)) + (log(t) * (a - 0.5))) - t;
	} else {
		tmp = (a * log(t)) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (log(z) <= 230.0d0) then
        tmp = (log((y * z)) + (log(t) * (a - 0.5d0))) - t
    else
        tmp = (a * log(t)) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (Math.log(z) <= 230.0) {
		tmp = (Math.log((y * z)) + (Math.log(t) * (a - 0.5))) - t;
	} else {
		tmp = (a * Math.log(t)) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if math.log(z) <= 230.0:
		tmp = (math.log((y * z)) + (math.log(t) * (a - 0.5))) - t
	else:
		tmp = (a * math.log(t)) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (log(z) <= 230.0)
		tmp = Float64(Float64(log(Float64(y * z)) + Float64(log(t) * Float64(a - 0.5))) - t);
	else
		tmp = Float64(Float64(a * log(t)) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (log(z) <= 230.0)
		tmp = (log((y * z)) + (log(t) * (a - 0.5))) - t;
	else
		tmp = (a * log(t)) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[N[Log[z], $MachinePrecision], 230.0], N[(N[(N[Log[N[(y * z), $MachinePrecision]], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\log z \leq 230:\\
\;\;\;\;\left(\log \left(y \cdot z\right) + \log t \cdot \left(a - 0.5\right)\right) - t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (log.f64 z) < 230

    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%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log z + \left(\log \left(x + y\right) - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
    4. Step-by-step derivation
      1. associate-+r-99.7%

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

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

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

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

        \[\leadsto \left(\color{blue}{\left(\log z + \log \left(x + y\right)\right)} - \log t \cdot \left(0.5 - a\right)\right) - t \]
      6. sum-log96.2%

        \[\leadsto \left(\color{blue}{\log \left(z \cdot \left(x + y\right)\right)} - \log t \cdot \left(0.5 - a\right)\right) - t \]
    5. Applied egg-rr96.2%

      \[\leadsto \color{blue}{\left(\log \left(z \cdot \left(x + y\right)\right) - \log t \cdot \left(0.5 - a\right)\right) - t} \]
    6. Taylor expanded in x around 0 62.7%

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

    if 230 < (log.f64 z)

    1. Initial program 99.6%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 63.0%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \left(\log t \cdot \left(a - 0.5\right) + \frac{x}{y}\right)\right)\right) - t} \]
    3. Taylor expanded in a around inf 80.5%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    4. Step-by-step derivation
      1. *-commutative80.5%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    5. Simplified80.5%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification69.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\log z \leq 230:\\ \;\;\;\;\left(\log \left(y \cdot z\right) + \log t \cdot \left(a - 0.5\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \]

Alternative 6: 69.3% accurate, 1.0× speedup?

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

\\
\log z + \left(\log y - \left(t + \log t \cdot \left(0.5 - a\right)\right)\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. 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. +-commutative99.6%

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

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

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

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

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

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

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

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

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

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

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

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

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

    \[\leadsto \color{blue}{\log z + \left(\log \left(x + y\right) - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
  4. Taylor expanded in x around 0 70.4%

    \[\leadsto \log z + \color{blue}{\left(\log y - \left(t + \log t \cdot \left(0.5 - a\right)\right)\right)} \]
  5. Final simplification70.4%

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

Alternative 7: 69.3% 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. Taylor expanded in x around 0 61.4%

    \[\leadsto \color{blue}{\left(\log y + \left(\log z + \left(\log t \cdot \left(a - 0.5\right) + \frac{x}{y}\right)\right)\right) - t} \]
  3. Taylor expanded in x around 0 70.5%

    \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right)} - t \]
  4. Final simplification70.5%

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

Alternative 8: 73.9% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -1.6 \lor \neg \left(a \leq 0.49\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log t \cdot -0.5 + \log \left(y \cdot z\right)\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (or (<= a -1.6) (not (<= a 0.49)))
   (- (* a (log t)) t)
   (- (+ (* (log t) -0.5) (log (* y z))) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a <= -1.6) || !(a <= 0.49)) {
		tmp = (a * log(t)) - t;
	} else {
		tmp = ((log(t) * -0.5) + log((y * 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 <= (-1.6d0)) .or. (.not. (a <= 0.49d0))) then
        tmp = (a * log(t)) - t
    else
        tmp = ((log(t) * (-0.5d0)) + log((y * 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 <= -1.6) || !(a <= 0.49)) {
		tmp = (a * Math.log(t)) - t;
	} else {
		tmp = ((Math.log(t) * -0.5) + Math.log((y * z))) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if (a <= -1.6) or not (a <= 0.49):
		tmp = (a * math.log(t)) - t
	else:
		tmp = ((math.log(t) * -0.5) + math.log((y * z))) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if ((a <= -1.6) || !(a <= 0.49))
		tmp = Float64(Float64(a * log(t)) - t);
	else
		tmp = Float64(Float64(Float64(log(t) * -0.5) + log(Float64(y * z))) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if ((a <= -1.6) || ~((a <= 0.49)))
		tmp = (a * log(t)) - t;
	else
		tmp = ((log(t) * -0.5) + log((y * z))) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[Or[LessEqual[a, -1.6], N[Not[LessEqual[a, 0.49]], $MachinePrecision]], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(N[(N[Log[t], $MachinePrecision] * -0.5), $MachinePrecision] + N[Log[N[(y * z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -1.6 \lor \neg \left(a \leq 0.49\right):\\
\;\;\;\;a \cdot \log t - t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -1.6000000000000001 or 0.48999999999999999 < a

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 64.2%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \left(\log t \cdot \left(a - 0.5\right) + \frac{x}{y}\right)\right)\right) - t} \]
    3. Taylor expanded in a around inf 98.7%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    4. Step-by-step derivation
      1. *-commutative98.7%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    5. Simplified98.7%

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

    if -1.6000000000000001 < a < 0.48999999999999999

    1. Initial program 99.5%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in a around 0 97.5%

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

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + -0.5 \cdot \log t\right)\right)} - t \]
    4. Step-by-step derivation
      1. associate-+r+65.8%

        \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) + -0.5 \cdot \log t\right)} - t \]
      2. log-prod50.1%

        \[\leadsto \left(\color{blue}{\log \left(y \cdot z\right)} + -0.5 \cdot \log t\right) - t \]
      3. *-commutative50.1%

        \[\leadsto \left(\log \left(y \cdot z\right) + \color{blue}{\log t \cdot -0.5}\right) - t \]
    5. Simplified50.1%

      \[\leadsto \color{blue}{\left(\log \left(y \cdot z\right) + \log t \cdot -0.5\right)} - t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification76.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -1.6 \lor \neg \left(a \leq 0.49\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log t \cdot -0.5 + \log \left(y \cdot z\right)\right) - t\\ \end{array} \]

Alternative 9: 87.1% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 0.135:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 0.135)
   (+ (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 <= 0.135) {
		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 <= 0.135d0) 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 <= 0.135) {
		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 <= 0.135:
		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 <= 0.135)
		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 <= 0.135)
		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, 0.135], 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 0.135:\\
\;\;\;\;\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 < 0.13500000000000001

    1. Initial program 99.4%

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

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

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

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

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

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

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

        \[\leadsto \log z + \left(\log \left(x + y\right) - \left(\color{blue}{\log t \cdot \left(-\left(a - 0.5\right)\right)} + t\right)\right) \]
      8. fma-def99.2%

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\log z + \log \left(x + y\right)\right) - \log t \cdot \left(0.5 - a\right)} \]
    5. Step-by-step derivation
      1. log-prod80.6%

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

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

    if 0.13500000000000001 < t

    1. Initial program 99.9%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 59.2%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \left(\log t \cdot \left(a - 0.5\right) + \frac{x}{y}\right)\right)\right) - t} \]
    3. Taylor expanded in a around inf 99.0%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    4. Step-by-step derivation
      1. *-commutative99.0%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    5. Simplified99.0%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification89.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 0.135:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \log t \cdot \left(a - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \]

Alternative 10: 72.1% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -0.0075 \lor \neg \left(a \leq 0.41\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\log \left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (or (<= a -0.0075) (not (<= a 0.41)))
   (- (* a (log t)) t)
   (- (log (* y (* z (pow t -0.5)))) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a <= -0.0075) || !(a <= 0.41)) {
		tmp = (a * log(t)) - t;
	} else {
		tmp = log((y * (z * pow(t, -0.5)))) - 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 <= (-0.0075d0)) .or. (.not. (a <= 0.41d0))) then
        tmp = (a * log(t)) - t
    else
        tmp = log((y * (z * (t ** (-0.5d0))))) - 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 <= -0.0075) || !(a <= 0.41)) {
		tmp = (a * Math.log(t)) - t;
	} else {
		tmp = Math.log((y * (z * Math.pow(t, -0.5)))) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if (a <= -0.0075) or not (a <= 0.41):
		tmp = (a * math.log(t)) - t
	else:
		tmp = math.log((y * (z * math.pow(t, -0.5)))) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if ((a <= -0.0075) || !(a <= 0.41))
		tmp = Float64(Float64(a * log(t)) - t);
	else
		tmp = Float64(log(Float64(y * Float64(z * (t ^ -0.5)))) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if ((a <= -0.0075) || ~((a <= 0.41)))
		tmp = (a * log(t)) - t;
	else
		tmp = log((y * (z * (t ^ -0.5)))) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[Or[LessEqual[a, -0.0075], N[Not[LessEqual[a, 0.41]], $MachinePrecision]], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[Log[N[(y * N[(z * N[Power[t, -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -0.0075 \lor \neg \left(a \leq 0.41\right):\\
\;\;\;\;a \cdot \log t - t\\

\mathbf{else}:\\
\;\;\;\;\log \left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right) - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -0.0074999999999999997 or 0.409999999999999976 < a

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 63.7%

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

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    4. Step-by-step derivation
      1. *-commutative98.8%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    5. Simplified98.8%

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

    if -0.0074999999999999997 < a < 0.409999999999999976

    1. Initial program 99.5%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in a around 0 97.5%

      \[\leadsto \color{blue}{\left(\log z + \left(\log \left(x + y\right) + -0.5 \cdot \log t\right)\right) - t} \]
    3. Step-by-step derivation
      1. associate-+r+97.7%

        \[\leadsto \color{blue}{\left(\left(\log z + \log \left(x + y\right)\right) + -0.5 \cdot \log t\right)} - t \]
      2. log-prod77.7%

        \[\leadsto \left(\color{blue}{\log \left(z \cdot \left(x + y\right)\right)} + -0.5 \cdot \log t\right) - t \]
      3. add-log-exp77.7%

        \[\leadsto \left(\log \left(z \cdot \left(x + y\right)\right) + \color{blue}{\log \left(e^{-0.5 \cdot \log t}\right)}\right) - t \]
      4. sum-log70.5%

        \[\leadsto \color{blue}{\log \left(\left(z \cdot \left(x + y\right)\right) \cdot e^{-0.5 \cdot \log t}\right)} - t \]
      5. +-commutative70.5%

        \[\leadsto \log \left(\left(z \cdot \color{blue}{\left(y + x\right)}\right) \cdot e^{-0.5 \cdot \log t}\right) - t \]
      6. *-commutative70.5%

        \[\leadsto \log \left(\left(z \cdot \left(y + x\right)\right) \cdot e^{\color{blue}{\log t \cdot -0.5}}\right) - t \]
      7. exp-to-pow70.6%

        \[\leadsto \log \left(\left(z \cdot \left(y + x\right)\right) \cdot \color{blue}{{t}^{-0.5}}\right) - t \]
    4. Applied egg-rr70.6%

      \[\leadsto \color{blue}{\log \left(\left(z \cdot \left(y + x\right)\right) \cdot {t}^{-0.5}\right)} - t \]
    5. Taylor expanded in y around inf 46.7%

      \[\leadsto \log \left(\color{blue}{\left(y \cdot z\right)} \cdot {t}^{-0.5}\right) - t \]
    6. Step-by-step derivation
      1. expm1-log1p-u46.7%

        \[\leadsto \log \color{blue}{\left(\mathsf{expm1}\left(\mathsf{log1p}\left(\left(y \cdot z\right) \cdot {t}^{-0.5}\right)\right)\right)} - t \]
      2. expm1-udef28.6%

        \[\leadsto \log \color{blue}{\left(e^{\mathsf{log1p}\left(\left(y \cdot z\right) \cdot {t}^{-0.5}\right)} - 1\right)} - t \]
      3. associate-*l*31.8%

        \[\leadsto \log \left(e^{\mathsf{log1p}\left(\color{blue}{y \cdot \left(z \cdot {t}^{-0.5}\right)}\right)} - 1\right) - t \]
    7. Applied egg-rr31.8%

      \[\leadsto \log \color{blue}{\left(e^{\mathsf{log1p}\left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right)} - 1\right)} - t \]
    8. Step-by-step derivation
      1. expm1-def49.1%

        \[\leadsto \log \color{blue}{\left(\mathsf{expm1}\left(\mathsf{log1p}\left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right)\right)\right)} - t \]
      2. expm1-log1p49.1%

        \[\leadsto \log \color{blue}{\left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right)} - t \]
    9. Simplified49.1%

      \[\leadsto \log \color{blue}{\left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right)} - t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification75.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -0.0075 \lor \neg \left(a \leq 0.41\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\log \left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right) - t\\ \end{array} \]

Alternative 11: 78.6% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -1450000000 \lor \neg \left(a \leq 2.2\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\log z + \left(\log \left(x + y\right) - t\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (or (<= a -1450000000.0) (not (<= a 2.2)))
   (- (* a (log t)) t)
   (+ (log z) (- (log (+ x y)) t))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if ((a <= -1450000000.0) || !(a <= 2.2)) {
		tmp = (a * log(t)) - t;
	} else {
		tmp = log(z) + (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 <= (-1450000000.0d0)) .or. (.not. (a <= 2.2d0))) then
        tmp = (a * log(t)) - t
    else
        tmp = log(z) + (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 <= -1450000000.0) || !(a <= 2.2)) {
		tmp = (a * Math.log(t)) - t;
	} else {
		tmp = Math.log(z) + (Math.log((x + y)) - t);
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if (a <= -1450000000.0) or not (a <= 2.2):
		tmp = (a * math.log(t)) - t
	else:
		tmp = math.log(z) + (math.log((x + y)) - t)
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if ((a <= -1450000000.0) || !(a <= 2.2))
		tmp = Float64(Float64(a * log(t)) - t);
	else
		tmp = Float64(log(z) + Float64(log(Float64(x + y)) - t));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if ((a <= -1450000000.0) || ~((a <= 2.2)))
		tmp = (a * log(t)) - t;
	else
		tmp = log(z) + (log((x + y)) - t);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[Or[LessEqual[a, -1450000000.0], N[Not[LessEqual[a, 2.2]], $MachinePrecision]], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[Log[z], $MachinePrecision] + N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -1450000000 \lor \neg \left(a \leq 2.2\right):\\
\;\;\;\;a \cdot \log t - t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -1.45e9 or 2.2000000000000002 < a

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Taylor expanded in x around 0 63.9%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \left(\log t \cdot \left(a - 0.5\right) + \frac{x}{y}\right)\right)\right) - t} \]
    3. Taylor expanded in a around inf 98.7%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    4. Step-by-step derivation
      1. *-commutative98.7%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    5. Simplified98.7%

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

    if -1.45e9 < a < 2.2000000000000002

    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. +-commutative99.5%

        \[\leadsto \color{blue}{\left(\log z + \log \left(x + y\right)\right)} - \left(t - \left(a - 0.5\right) \cdot \log t\right) \]
      3. associate--l+99.4%

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

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

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

        \[\leadsto \log z + \left(\log \left(x + y\right) - \left(\left(-\color{blue}{\log t \cdot \left(a - 0.5\right)}\right) + t\right)\right) \]
      7. distribute-rgt-neg-in99.4%

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

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

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

        \[\leadsto \log z + \left(\log \left(x + y\right) - \mathsf{fma}\left(\log t, -\color{blue}{\left(\left(-0.5\right) + a\right)}, t\right)\right) \]
      11. distribute-neg-in99.4%

        \[\leadsto \log z + \left(\log \left(x + y\right) - \mathsf{fma}\left(\log t, \color{blue}{\left(-\left(-0.5\right)\right) + \left(-a\right)}, t\right)\right) \]
      12. metadata-eval99.4%

        \[\leadsto \log z + \left(\log \left(x + y\right) - \mathsf{fma}\left(\log t, \left(-\color{blue}{-0.5}\right) + \left(-a\right), t\right)\right) \]
      13. metadata-eval99.4%

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

        \[\leadsto \log z + \left(\log \left(x + y\right) - \mathsf{fma}\left(\log t, \color{blue}{0.5 - a}, t\right)\right) \]
    3. Simplified99.4%

      \[\leadsto \color{blue}{\log z + \left(\log \left(x + y\right) - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
    4. Taylor expanded in t around inf 59.6%

      \[\leadsto \log z + \left(\log \left(x + y\right) - \color{blue}{t}\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification80.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -1450000000 \lor \neg \left(a \leq 2.2\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\log z + \left(\log \left(x + y\right) - t\right)\\ \end{array} \]

Alternative 12: 62.8% accurate, 3.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 1.52 \cdot 10^{+18}:\\ \;\;\;\;a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 1.52e+18) (* a (log t)) (- t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 1.52e+18) {
		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 <= 1.52d+18) 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 <= 1.52e+18) {
		tmp = a * Math.log(t);
	} else {
		tmp = -t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 1.52e+18:
		tmp = a * math.log(t)
	else:
		tmp = -t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 1.52e+18)
		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 <= 1.52e+18)
		tmp = a * log(t);
	else
		tmp = -t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 1.52e+18], N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision], (-t)]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 1.52 \cdot 10^{+18}:\\
\;\;\;\;a \cdot \log t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 1.52e18

    1. Initial program 99.4%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log z + \left(\log \left(x + y\right) - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
    4. Taylor expanded in a around inf 57.8%

      \[\leadsto \color{blue}{a \cdot \log t} \]
    5. Step-by-step derivation
      1. *-commutative57.8%

        \[\leadsto \color{blue}{\log t \cdot a} \]
    6. Simplified57.8%

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

    if 1.52e18 < 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. +-commutative99.9%

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

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log z + \left(\log \left(x + y\right) - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
    4. Taylor expanded in t around inf 82.3%

      \[\leadsto \color{blue}{-1 \cdot t} \]
    5. Step-by-step derivation
      1. neg-mul-182.3%

        \[\leadsto \color{blue}{-t} \]
    6. Simplified82.3%

      \[\leadsto \color{blue}{-t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification68.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 1.52 \cdot 10^{+18}:\\ \;\;\;\;a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]

Alternative 13: 74.9% 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. Taylor expanded in x around 0 61.4%

    \[\leadsto \color{blue}{\left(\log y + \left(\log z + \left(\log t \cdot \left(a - 0.5\right) + \frac{x}{y}\right)\right)\right) - t} \]
  3. Taylor expanded in a around inf 77.0%

    \[\leadsto \color{blue}{a \cdot \log t} - t \]
  4. Step-by-step derivation
    1. *-commutative77.0%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  5. Simplified77.0%

    \[\leadsto \color{blue}{\log t \cdot a} - t \]
  6. Final simplification77.0%

    \[\leadsto a \cdot \log t - t \]

Alternative 14: 29.1% accurate, 62.6× speedup?

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

\\
\frac{x}{y} - 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. Taylor expanded in x around 0 61.4%

    \[\leadsto \color{blue}{\left(\log y + \left(\log z + \left(\log t \cdot \left(a - 0.5\right) + \frac{x}{y}\right)\right)\right) - t} \]
  3. Taylor expanded in y around 0 27.6%

    \[\leadsto \color{blue}{\frac{x}{y}} - t \]
  4. Final simplification27.6%

    \[\leadsto \frac{x}{y} - t \]

Alternative 15: 37.9% 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. +-commutative99.6%

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

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

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

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

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

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

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

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

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

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

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

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

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

    \[\leadsto \color{blue}{\log z + \left(\log \left(x + y\right) - \mathsf{fma}\left(\log t, 0.5 - a, t\right)\right)} \]
  4. Taylor expanded in t around inf 38.5%

    \[\leadsto \color{blue}{-1 \cdot t} \]
  5. Step-by-step derivation
    1. neg-mul-138.5%

      \[\leadsto \color{blue}{-t} \]
  6. Simplified38.5%

    \[\leadsto \color{blue}{-t} \]
  7. Final simplification38.5%

    \[\leadsto -t \]

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 2023336 
(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))))