Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 12.0s
Alternatives: 13
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 13 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?

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

Alternative 2: 93.9% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ \mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 710\right):\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (+ (log (+ x y)) (log z))))
   (if (or (<= t_1 -750.0) (not (<= t_1 710.0)))
     (+ (pow (/ -1.0 t) -1.0) (* (- a 0.5) (log t)))
     (- (log (* z (+ y x))) (- t (* (log t) (- a 0.5)))))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = log((x + y)) + log(z);
	double tmp;
	if ((t_1 <= -750.0) || !(t_1 <= 710.0)) {
		tmp = pow((-1.0 / t), -1.0) + ((a - 0.5) * log(t));
	} else {
		tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5)));
	}
	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)) + log(z)
    if ((t_1 <= (-750.0d0)) .or. (.not. (t_1 <= 710.0d0))) then
        tmp = (((-1.0d0) / t) ** (-1.0d0)) + ((a - 0.5d0) * log(t))
    else
        tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5d0)))
    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)) + Math.log(z);
	double tmp;
	if ((t_1 <= -750.0) || !(t_1 <= 710.0)) {
		tmp = Math.pow((-1.0 / t), -1.0) + ((a - 0.5) * Math.log(t));
	} else {
		tmp = Math.log((z * (y + x))) - (t - (Math.log(t) * (a - 0.5)));
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = math.log((x + y)) + math.log(z)
	tmp = 0
	if (t_1 <= -750.0) or not (t_1 <= 710.0):
		tmp = math.pow((-1.0 / t), -1.0) + ((a - 0.5) * math.log(t))
	else:
		tmp = math.log((z * (y + x))) - (t - (math.log(t) * (a - 0.5)))
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(log(Float64(x + y)) + log(z))
	tmp = 0.0
	if ((t_1 <= -750.0) || !(t_1 <= 710.0))
		tmp = Float64((Float64(-1.0 / t) ^ -1.0) + Float64(Float64(a - 0.5) * log(t)));
	else
		tmp = Float64(log(Float64(z * Float64(y + x))) - Float64(t - Float64(log(t) * Float64(a - 0.5))));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = log((x + y)) + log(z);
	tmp = 0.0;
	if ((t_1 <= -750.0) || ~((t_1 <= 710.0)))
		tmp = ((-1.0 / t) ^ -1.0) + ((a - 0.5) * log(t));
	else
		tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5)));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$1, -750.0], N[Not[LessEqual[t$95$1, 710.0]], $MachinePrecision]], N[(N[Power[N[(-1.0 / t), $MachinePrecision], -1.0], $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - N[(t - N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \log \left(x + y\right) + \log z\\
\mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 710\right):\\
\;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -750 or 710 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

    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. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      2. flip--N/A

        \[\leadsto \color{blue}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      3. clear-numN/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      5. clear-numN/A

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      6. flip--N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      7. lift--.f64N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      8. lower-/.f6499.6

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - 0.5\right) \cdot \log t \]
    4. Applied rewrites2.3%

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

      \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
    6. Step-by-step derivation
      1. lower-/.f6481.9

        \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]
    7. Applied rewrites81.9%

      \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]

    if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 710

    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. Step-by-step derivation
      1. lift-+.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - \frac{1}{2}\right) \cdot \log t} \]
      2. lift--.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      3. associate-+l-N/A

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right)} \]
      4. lower--.f64N/A

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right)} \]
      5. lift-+.f64N/A

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      6. lift-log.f64N/A

        \[\leadsto \left(\color{blue}{\log \left(x + y\right)} + \log z\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      7. lift-log.f64N/A

        \[\leadsto \left(\log \left(x + y\right) + \color{blue}{\log z}\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      8. sum-logN/A

        \[\leadsto \color{blue}{\log \left(\left(x + y\right) \cdot z\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      9. lower-log.f64N/A

        \[\leadsto \color{blue}{\log \left(\left(x + y\right) \cdot z\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      10. *-commutativeN/A

        \[\leadsto \log \color{blue}{\left(z \cdot \left(x + y\right)\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      11. lower-*.f64N/A

        \[\leadsto \log \color{blue}{\left(z \cdot \left(x + y\right)\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      12. lift-+.f64N/A

        \[\leadsto \log \left(z \cdot \color{blue}{\left(x + y\right)}\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      13. +-commutativeN/A

        \[\leadsto \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      14. lower-+.f64N/A

        \[\leadsto \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      15. lower--.f6499.7

        \[\leadsto \log \left(z \cdot \left(y + x\right)\right) - \color{blue}{\left(t - \left(a - 0.5\right) \cdot \log t\right)} \]
      16. lift-*.f64N/A

        \[\leadsto \log \left(z \cdot \left(y + x\right)\right) - \left(t - \color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t}\right) \]
      17. *-commutativeN/A

        \[\leadsto \log \left(z \cdot \left(y + x\right)\right) - \left(t - \color{blue}{\log t \cdot \left(a - \frac{1}{2}\right)}\right) \]
      18. lower-*.f6499.7

        \[\leadsto \log \left(z \cdot \left(y + x\right)\right) - \left(t - \color{blue}{\log t \cdot \left(a - 0.5\right)}\right) \]
    4. Applied rewrites99.7%

      \[\leadsto \color{blue}{\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification96.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq -750 \lor \neg \left(\log \left(x + y\right) + \log z \leq 710\right):\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 93.9% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ \mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 710\right):\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \left(y + x\right)\right)\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (+ (log (+ x y)) (log z))))
   (if (or (<= t_1 -750.0) (not (<= t_1 710.0)))
     (+ (pow (/ -1.0 t) -1.0) (* (- a 0.5) (log t)))
     (- (fma (log t) (- a 0.5) (log (* z (+ y x)))) t))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = log((x + y)) + log(z);
	double tmp;
	if ((t_1 <= -750.0) || !(t_1 <= 710.0)) {
		tmp = pow((-1.0 / t), -1.0) + ((a - 0.5) * log(t));
	} else {
		tmp = fma(log(t), (a - 0.5), log((z * (y + x)))) - t;
	}
	return tmp;
}
function code(x, y, z, t, a)
	t_1 = Float64(log(Float64(x + y)) + log(z))
	tmp = 0.0
	if ((t_1 <= -750.0) || !(t_1 <= 710.0))
		tmp = Float64((Float64(-1.0 / t) ^ -1.0) + Float64(Float64(a - 0.5) * log(t)));
	else
		tmp = Float64(fma(log(t), Float64(a - 0.5), log(Float64(z * Float64(y + x)))) - t);
	end
	return tmp
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$1, -750.0], N[Not[LessEqual[t$95$1, 710.0]], $MachinePrecision]], N[(N[Power[N[(-1.0 / t), $MachinePrecision], -1.0], $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \log \left(x + y\right) + \log z\\
\mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 710\right):\\
\;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -750 or 710 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

    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. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      2. flip--N/A

        \[\leadsto \color{blue}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      3. clear-numN/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      5. clear-numN/A

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      6. flip--N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      7. lift--.f64N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      8. lower-/.f6499.6

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - 0.5\right) \cdot \log t \]
    4. Applied rewrites2.3%

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

      \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
    6. Step-by-step derivation
      1. lower-/.f6481.9

        \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]
    7. Applied rewrites81.9%

      \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]

    if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 710

    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. Step-by-step derivation
      1. lift-+.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - \frac{1}{2}\right) \cdot \log t} \]
      2. +-commutativeN/A

        \[\leadsto \color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t + \left(\left(\log \left(x + y\right) + \log z\right) - t\right)} \]
      3. lift--.f64N/A

        \[\leadsto \left(a - \frac{1}{2}\right) \cdot \log t + \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} \]
      4. associate-+r-N/A

        \[\leadsto \color{blue}{\left(\left(a - \frac{1}{2}\right) \cdot \log t + \left(\log \left(x + y\right) + \log z\right)\right) - t} \]
      5. lower--.f64N/A

        \[\leadsto \color{blue}{\left(\left(a - \frac{1}{2}\right) \cdot \log t + \left(\log \left(x + y\right) + \log z\right)\right) - t} \]
      6. lift-*.f64N/A

        \[\leadsto \left(\color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t} + \left(\log \left(x + y\right) + \log z\right)\right) - t \]
      7. *-commutativeN/A

        \[\leadsto \left(\color{blue}{\log t \cdot \left(a - \frac{1}{2}\right)} + \left(\log \left(x + y\right) + \log z\right)\right) - t \]
      8. lower-fma.f6499.6

        \[\leadsto \color{blue}{\mathsf{fma}\left(\log t, a - 0.5, \log \left(x + y\right) + \log z\right)} - t \]
      9. lift-+.f64N/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \color{blue}{\log \left(x + y\right) + \log z}\right) - t \]
      10. lift-log.f64N/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \color{blue}{\log \left(x + y\right)} + \log z\right) - t \]
      11. lift-log.f64N/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(x + y\right) + \color{blue}{\log z}\right) - t \]
      12. sum-logN/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \color{blue}{\log \left(\left(x + y\right) \cdot z\right)}\right) - t \]
      13. lower-log.f64N/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \color{blue}{\log \left(\left(x + y\right) \cdot z\right)}\right) - t \]
      14. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \color{blue}{\left(z \cdot \left(x + y\right)\right)}\right) - t \]
      15. lower-*.f6499.7

        \[\leadsto \mathsf{fma}\left(\log t, a - 0.5, \log \color{blue}{\left(z \cdot \left(x + y\right)\right)}\right) - t \]
      16. lift-+.f64N/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(z \cdot \color{blue}{\left(x + y\right)}\right)\right) - t \]
      17. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right)\right) - t \]
      18. lower-+.f6499.7

        \[\leadsto \mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right)\right) - t \]
    4. Applied rewrites99.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \left(y + x\right)\right)\right) - t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification96.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq -750 \lor \neg \left(\log \left(x + y\right) + \log z \leq 710\right):\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \left(y + x\right)\right)\right) - t\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 68.9% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ t_2 := \left(a - 0.5\right) \cdot \log t\\ \mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 710\right):\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + t\_2\\ \mathbf{else}:\\ \;\;\;\;\log \left(z \cdot y\right) - \left(t - t\_2\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (+ (log (+ x y)) (log z))) (t_2 (* (- a 0.5) (log t))))
   (if (or (<= t_1 -750.0) (not (<= t_1 710.0)))
     (+ (pow (/ -1.0 t) -1.0) t_2)
     (- (log (* z y)) (- t t_2)))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = log((x + y)) + log(z);
	double t_2 = (a - 0.5) * log(t);
	double tmp;
	if ((t_1 <= -750.0) || !(t_1 <= 710.0)) {
		tmp = pow((-1.0 / t), -1.0) + t_2;
	} else {
		tmp = log((z * y)) - (t - t_2);
	}
	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) :: t_2
    real(8) :: tmp
    t_1 = log((x + y)) + log(z)
    t_2 = (a - 0.5d0) * log(t)
    if ((t_1 <= (-750.0d0)) .or. (.not. (t_1 <= 710.0d0))) then
        tmp = (((-1.0d0) / t) ** (-1.0d0)) + t_2
    else
        tmp = log((z * y)) - (t - t_2)
    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)) + Math.log(z);
	double t_2 = (a - 0.5) * Math.log(t);
	double tmp;
	if ((t_1 <= -750.0) || !(t_1 <= 710.0)) {
		tmp = Math.pow((-1.0 / t), -1.0) + t_2;
	} else {
		tmp = Math.log((z * y)) - (t - t_2);
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = math.log((x + y)) + math.log(z)
	t_2 = (a - 0.5) * math.log(t)
	tmp = 0
	if (t_1 <= -750.0) or not (t_1 <= 710.0):
		tmp = math.pow((-1.0 / t), -1.0) + t_2
	else:
		tmp = math.log((z * y)) - (t - t_2)
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(log(Float64(x + y)) + log(z))
	t_2 = Float64(Float64(a - 0.5) * log(t))
	tmp = 0.0
	if ((t_1 <= -750.0) || !(t_1 <= 710.0))
		tmp = Float64((Float64(-1.0 / t) ^ -1.0) + t_2);
	else
		tmp = Float64(log(Float64(z * y)) - Float64(t - t_2));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = log((x + y)) + log(z);
	t_2 = (a - 0.5) * log(t);
	tmp = 0.0;
	if ((t_1 <= -750.0) || ~((t_1 <= 710.0)))
		tmp = ((-1.0 / t) ^ -1.0) + t_2;
	else
		tmp = log((z * y)) - (t - t_2);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$1, -750.0], N[Not[LessEqual[t$95$1, 710.0]], $MachinePrecision]], N[(N[Power[N[(-1.0 / t), $MachinePrecision], -1.0], $MachinePrecision] + t$95$2), $MachinePrecision], N[(N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision] - N[(t - t$95$2), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \log \left(x + y\right) + \log z\\
t_2 := \left(a - 0.5\right) \cdot \log t\\
\mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 710\right):\\
\;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + t\_2\\

\mathbf{else}:\\
\;\;\;\;\log \left(z \cdot y\right) - \left(t - t\_2\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -750 or 710 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

    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. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      2. flip--N/A

        \[\leadsto \color{blue}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      3. clear-numN/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      5. clear-numN/A

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      6. flip--N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      7. lift--.f64N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      8. lower-/.f6499.6

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - 0.5\right) \cdot \log t \]
    4. Applied rewrites2.3%

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

      \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
    6. Step-by-step derivation
      1. lower-/.f6481.9

        \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]
    7. Applied rewrites81.9%

      \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]

    if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 710

    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. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t} \]
      2. *-commutativeN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\log t \cdot \left(a - \frac{1}{2}\right)} \]
      3. lift--.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\left(a - \frac{1}{2}\right)} \]
      4. flip3--N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\frac{{a}^{3} - {\frac{1}{2}}^{3}}{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}} \]
      5. clear-numN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\frac{1}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
      6. un-div-invN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
      7. lower-/.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
      8. clear-numN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{\frac{{a}^{3} - {\frac{1}{2}}^{3}}{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}}}} \]
      9. flip3--N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\frac{1}{\color{blue}{a - \frac{1}{2}}}} \]
      10. lift--.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\frac{1}{\color{blue}{a - \frac{1}{2}}}} \]
      11. lower-/.f6499.6

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
    4. Applied rewrites99.6%

      \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
    5. Step-by-step derivation
      1. lift-+.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\frac{1}{a - \frac{1}{2}}}} \]
      2. lift--.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \frac{\log t}{\frac{1}{a - \frac{1}{2}}} \]
      3. lift-/.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - \frac{1}{2}}}} \]
      4. div-invN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\log t \cdot \frac{1}{\frac{1}{a - \frac{1}{2}}}} \]
      5. lift-/.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \frac{1}{\color{blue}{\frac{1}{a - \frac{1}{2}}}} \]
      6. remove-double-divN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\left(a - \frac{1}{2}\right)} \]
      7. *-commutativeN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t} \]
      8. lift-*.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t} \]
      9. associate-+l-N/A

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right)} \]
      10. lift-+.f64N/A

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      11. +-commutativeN/A

        \[\leadsto \color{blue}{\left(\log z + \log \left(x + y\right)\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      12. lift-log.f64N/A

        \[\leadsto \left(\color{blue}{\log z} + \log \left(x + y\right)\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      13. lift-log.f64N/A

        \[\leadsto \left(\log z + \color{blue}{\log \left(x + y\right)}\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      14. lift-+.f64N/A

        \[\leadsto \left(\log z + \log \color{blue}{\left(x + y\right)}\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      15. +-commutativeN/A

        \[\leadsto \left(\log z + \log \color{blue}{\left(y + x\right)}\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      16. lift-+.f64N/A

        \[\leadsto \left(\log z + \log \color{blue}{\left(y + x\right)}\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      17. log-prodN/A

        \[\leadsto \color{blue}{\log \left(z \cdot \left(y + x\right)\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      18. lift-*.f64N/A

        \[\leadsto \log \color{blue}{\left(z \cdot \left(y + x\right)\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      19. lift-log.f64N/A

        \[\leadsto \color{blue}{\log \left(z \cdot \left(y + x\right)\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
    6. Applied rewrites99.7%

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

      \[\leadsto \log \color{blue}{\left(y \cdot z\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
    8. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \log \color{blue}{\left(z \cdot y\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      2. lower-*.f6466.2

        \[\leadsto \log \color{blue}{\left(z \cdot y\right)} - \left(t - \left(a - 0.5\right) \cdot \log t\right) \]
    9. Applied rewrites66.2%

      \[\leadsto \log \color{blue}{\left(z \cdot y\right)} - \left(t - \left(a - 0.5\right) \cdot \log t\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification69.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq -750 \lor \neg \left(\log \left(x + y\right) + \log z \leq 710\right):\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\log \left(z \cdot y\right) - \left(t - \left(a - 0.5\right) \cdot \log t\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 68.9% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ \mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 710\right):\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (+ (log (+ x y)) (log z))))
   (if (or (<= t_1 -750.0) (not (<= t_1 710.0)))
     (+ (pow (/ -1.0 t) -1.0) (* (- a 0.5) (log t)))
     (- (fma (log t) (- a 0.5) (log (* z y))) t))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = log((x + y)) + log(z);
	double tmp;
	if ((t_1 <= -750.0) || !(t_1 <= 710.0)) {
		tmp = pow((-1.0 / t), -1.0) + ((a - 0.5) * log(t));
	} else {
		tmp = fma(log(t), (a - 0.5), log((z * y))) - t;
	}
	return tmp;
}
function code(x, y, z, t, a)
	t_1 = Float64(log(Float64(x + y)) + log(z))
	tmp = 0.0
	if ((t_1 <= -750.0) || !(t_1 <= 710.0))
		tmp = Float64((Float64(-1.0 / t) ^ -1.0) + Float64(Float64(a - 0.5) * log(t)));
	else
		tmp = Float64(fma(log(t), Float64(a - 0.5), log(Float64(z * y))) - t);
	end
	return tmp
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$1, -750.0], N[Not[LessEqual[t$95$1, 710.0]], $MachinePrecision]], N[(N[Power[N[(-1.0 / t), $MachinePrecision], -1.0], $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \log \left(x + y\right) + \log z\\
\mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 710\right):\\
\;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right) - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -750 or 710 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

    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. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      2. flip--N/A

        \[\leadsto \color{blue}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      3. clear-numN/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      5. clear-numN/A

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      6. flip--N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      7. lift--.f64N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      8. lower-/.f6499.6

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - 0.5\right) \cdot \log t \]
    4. Applied rewrites2.3%

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

      \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
    6. Step-by-step derivation
      1. lower-/.f6481.9

        \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]
    7. Applied rewrites81.9%

      \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]

    if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 710

    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. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      2. flip--N/A

        \[\leadsto \color{blue}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      3. clear-numN/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      5. clear-numN/A

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      6. flip--N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      7. lift--.f64N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      8. lower-/.f6499.5

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - 0.5\right) \cdot \log t \]
    4. Applied rewrites99.6%

      \[\leadsto \color{blue}{\frac{1}{\frac{1}{\log \left(z \cdot \left(y + x\right)\right) - t}}} + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in x around 0

      \[\leadsto \color{blue}{\left(\log \left(y \cdot z\right) + \log t \cdot \left(a - \frac{1}{2}\right)\right) - t} \]
    6. Step-by-step derivation
      1. lower--.f64N/A

        \[\leadsto \color{blue}{\left(\log \left(y \cdot z\right) + \log t \cdot \left(a - \frac{1}{2}\right)\right) - t} \]
      2. +-commutativeN/A

        \[\leadsto \color{blue}{\left(\log t \cdot \left(a - \frac{1}{2}\right) + \log \left(y \cdot z\right)\right)} - t \]
      3. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(y \cdot z\right)\right)} - t \]
      4. lower-log.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\log t}, a - \frac{1}{2}, \log \left(y \cdot z\right)\right) - t \]
      5. lower--.f64N/A

        \[\leadsto \mathsf{fma}\left(\log t, \color{blue}{a - \frac{1}{2}}, \log \left(y \cdot z\right)\right) - t \]
      6. lower-log.f64N/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \color{blue}{\log \left(y \cdot z\right)}\right) - t \]
      7. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \color{blue}{\left(z \cdot y\right)}\right) - t \]
      8. lower-*.f6466.2

        \[\leadsto \mathsf{fma}\left(\log t, a - 0.5, \log \color{blue}{\left(z \cdot y\right)}\right) - t \]
    7. Applied rewrites66.2%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right) - t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification69.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq -750 \lor \neg \left(\log \left(x + y\right) + \log z \leq 710\right):\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right) - t\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 98.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 440:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(y + x\right)\right) + \log z\\ \mathbf{else}:\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 440.0)
   (+ (fma (- a 0.5) (log t) (log (+ y x))) (log z))
   (+ (pow (/ -1.0 t) -1.0) (* (- a 0.5) (log t)))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 440.0) {
		tmp = fma((a - 0.5), log(t), log((y + x))) + log(z);
	} else {
		tmp = pow((-1.0 / t), -1.0) + ((a - 0.5) * log(t));
	}
	return tmp;
}
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 440.0)
		tmp = Float64(fma(Float64(a - 0.5), log(t), log(Float64(y + x))) + log(z));
	else
		tmp = Float64((Float64(-1.0 / t) ^ -1.0) + Float64(Float64(a - 0.5) * log(t)));
	end
	return tmp
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 440.0], N[(N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[N[(y + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision], N[(N[Power[N[(-1.0 / t), $MachinePrecision], -1.0], $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 440:\\
\;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(y + x\right)\right) + \log z\\

\mathbf{else}:\\
\;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 440

    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. Add Preprocessing
    3. Taylor expanded in t around 0

      \[\leadsto \color{blue}{\log z + \left(\log \left(x + y\right) + \log t \cdot \left(a - \frac{1}{2}\right)\right)} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log t \cdot \left(a - \frac{1}{2}\right)\right) + \log z} \]
      2. lower-+.f64N/A

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log t \cdot \left(a - \frac{1}{2}\right)\right) + \log z} \]
      3. +-commutativeN/A

        \[\leadsto \color{blue}{\left(\log t \cdot \left(a - \frac{1}{2}\right) + \log \left(x + y\right)\right)} + \log z \]
      4. *-commutativeN/A

        \[\leadsto \left(\color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t} + \log \left(x + y\right)\right) + \log z \]
      5. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(a - \frac{1}{2}, \log t, \log \left(x + y\right)\right)} + \log z \]
      6. lower--.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{a - \frac{1}{2}}, \log t, \log \left(x + y\right)\right) + \log z \]
      7. lower-log.f64N/A

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \color{blue}{\log t}, \log \left(x + y\right)\right) + \log z \]
      8. lower-log.f64N/A

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \color{blue}{\log \left(x + y\right)}\right) + \log z \]
      9. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log \color{blue}{\left(y + x\right)}\right) + \log z \]
      10. lower-+.f64N/A

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log \color{blue}{\left(y + x\right)}\right) + \log z \]
      11. lower-log.f6499.0

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \left(y + x\right)\right) + \color{blue}{\log z} \]
    5. Applied rewrites99.0%

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

    if 440 < 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. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      2. flip--N/A

        \[\leadsto \color{blue}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      3. clear-numN/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      5. clear-numN/A

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      6. flip--N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      7. lift--.f64N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      8. lower-/.f6499.6

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - 0.5\right) \cdot \log t \]
    4. Applied rewrites78.5%

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

      \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
    6. Step-by-step derivation
      1. lower-/.f6498.5

        \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]
    7. Applied rewrites98.5%

      \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification98.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 440:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(y + x\right)\right) + \log z\\ \mathbf{else}:\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 81.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 440:\\ \;\;\;\;\mathsf{fma}\left(\log t, -0.5 + a, \log y\right) + \log z\\ \mathbf{else}:\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 440.0)
   (+ (fma (log t) (+ -0.5 a) (log y)) (log z))
   (+ (pow (/ -1.0 t) -1.0) (* (- a 0.5) (log t)))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 440.0) {
		tmp = fma(log(t), (-0.5 + a), log(y)) + log(z);
	} else {
		tmp = pow((-1.0 / t), -1.0) + ((a - 0.5) * log(t));
	}
	return tmp;
}
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 440.0)
		tmp = Float64(fma(log(t), Float64(-0.5 + a), log(y)) + log(z));
	else
		tmp = Float64((Float64(-1.0 / t) ^ -1.0) + Float64(Float64(a - 0.5) * log(t)));
	end
	return tmp
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 440.0], N[(N[(N[Log[t], $MachinePrecision] * N[(-0.5 + a), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision], N[(N[Power[N[(-1.0 / t), $MachinePrecision], -1.0], $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 440:\\
\;\;\;\;\mathsf{fma}\left(\log t, -0.5 + a, \log y\right) + \log z\\

\mathbf{else}:\\
\;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 440

    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. Add Preprocessing
    3. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t} \]
      2. *-commutativeN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\log t \cdot \left(a - \frac{1}{2}\right)} \]
      3. lift--.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\left(a - \frac{1}{2}\right)} \]
      4. flip3--N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\frac{{a}^{3} - {\frac{1}{2}}^{3}}{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}} \]
      5. clear-numN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\frac{1}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
      6. un-div-invN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
      7. lower-/.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
      8. clear-numN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{\frac{{a}^{3} - {\frac{1}{2}}^{3}}{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}}}} \]
      9. flip3--N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\frac{1}{\color{blue}{a - \frac{1}{2}}}} \]
      10. lift--.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\frac{1}{\color{blue}{a - \frac{1}{2}}}} \]
      11. lower-/.f6499.3

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
    4. Applied rewrites99.3%

      \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
    5. Taylor expanded in t around 0

      \[\leadsto \color{blue}{\log z + \left(\log \left(x + y\right) + \log t \cdot \left(a - \frac{1}{2}\right)\right)} \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log t \cdot \left(a - \frac{1}{2}\right)\right) + \log z} \]
      2. lower-+.f64N/A

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log t \cdot \left(a - \frac{1}{2}\right)\right) + \log z} \]
      3. +-commutativeN/A

        \[\leadsto \color{blue}{\left(\log t \cdot \left(a - \frac{1}{2}\right) + \log \left(x + y\right)\right)} + \log z \]
      4. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(x + y\right)\right)} + \log z \]
      5. lower-log.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\log t}, a - \frac{1}{2}, \log \left(x + y\right)\right) + \log z \]
      6. lower--.f64N/A

        \[\leadsto \mathsf{fma}\left(\log t, \color{blue}{a - \frac{1}{2}}, \log \left(x + y\right)\right) + \log z \]
      7. lower-log.f64N/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \color{blue}{\log \left(x + y\right)}\right) + \log z \]
      8. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \color{blue}{\left(y + x\right)}\right) + \log z \]
      9. lower-+.f64N/A

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \color{blue}{\left(y + x\right)}\right) + \log z \]
      10. lower-log.f6499.0

        \[\leadsto \mathsf{fma}\left(\log t, a - 0.5, \log \left(y + x\right)\right) + \color{blue}{\log z} \]
    7. Applied rewrites99.0%

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

      \[\leadsto \left(\log y + \log t \cdot \left(a - \frac{1}{2}\right)\right) + \log \color{blue}{z} \]
    9. Step-by-step derivation
      1. Applied rewrites61.4%

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

      if 440 < 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. Add Preprocessing
      3. Step-by-step derivation
        1. lift--.f64N/A

          \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        2. flip--N/A

          \[\leadsto \color{blue}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        3. clear-numN/A

          \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        4. lower-/.f64N/A

          \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        5. clear-numN/A

          \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        6. flip--N/A

          \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        7. lift--.f64N/A

          \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        8. lower-/.f6499.6

          \[\leadsto \frac{1}{\color{blue}{\frac{1}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - 0.5\right) \cdot \log t \]
      4. Applied rewrites78.5%

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

        \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      6. Step-by-step derivation
        1. lower-/.f6498.5

          \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]
      7. Applied rewrites98.5%

        \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]
    10. Recombined 2 regimes into one program.
    11. Final simplification82.1%

      \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 440:\\ \;\;\;\;\mathsf{fma}\left(\log t, -0.5 + a, \log y\right) + \log z\\ \mathbf{else}:\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t\\ \end{array} \]
    12. Add Preprocessing

    Alternative 8: 69.9% accurate, 1.0× speedup?

    \[\begin{array}{l} \\ \left(\log y + \log z\right) - \left(t - \left(a - 0.5\right) \cdot \log t\right) \end{array} \]
    (FPCore (x y z t a)
     :precision binary64
     (- (+ (log y) (log z)) (- t (* (- a 0.5) (log t)))))
    double code(double x, double y, double z, double t, double a) {
    	return (log(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(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(y) + Math.log(z)) - (t - ((a - 0.5) * Math.log(t)));
    }
    
    def code(x, y, z, t, a):
    	return (math.log(y) + math.log(z)) - (t - ((a - 0.5) * math.log(t)))
    
    function code(x, y, z, t, a)
    	return Float64(Float64(log(y) + log(z)) - Float64(t - Float64(Float64(a - 0.5) * log(t))))
    end
    
    function tmp = code(x, y, z, t, a)
    	tmp = (log(y) + log(z)) - (t - ((a - 0.5) * log(t)));
    end
    
    code[x_, y_, z_, t_, a_] := N[(N[(N[Log[y], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - N[(t - N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \left(\log y + \log z\right) - \left(t - \left(a - 0.5\right) \cdot \log t\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. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t} \]
      2. *-commutativeN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\log t \cdot \left(a - \frac{1}{2}\right)} \]
      3. lift--.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\left(a - \frac{1}{2}\right)} \]
      4. flip3--N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\frac{{a}^{3} - {\frac{1}{2}}^{3}}{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}} \]
      5. clear-numN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\frac{1}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
      6. un-div-invN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
      7. lower-/.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
      8. clear-numN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{\frac{{a}^{3} - {\frac{1}{2}}^{3}}{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}}}} \]
      9. flip3--N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\frac{1}{\color{blue}{a - \frac{1}{2}}}} \]
      10. lift--.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\frac{1}{\color{blue}{a - \frac{1}{2}}}} \]
      11. lower-/.f6499.6

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
    4. Applied rewrites99.6%

      \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
    5. Step-by-step derivation
      1. lift-+.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\frac{1}{a - \frac{1}{2}}}} \]
      2. lift--.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \frac{\log t}{\frac{1}{a - \frac{1}{2}}} \]
      3. lift-/.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - \frac{1}{2}}}} \]
      4. div-invN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\log t \cdot \frac{1}{\frac{1}{a - \frac{1}{2}}}} \]
      5. lift-/.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \frac{1}{\color{blue}{\frac{1}{a - \frac{1}{2}}}} \]
      6. remove-double-divN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\left(a - \frac{1}{2}\right)} \]
      7. *-commutativeN/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t} \]
      8. lift-*.f64N/A

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t} \]
      9. associate-+l-N/A

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right)} \]
      10. lift-+.f64N/A

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      11. +-commutativeN/A

        \[\leadsto \color{blue}{\left(\log z + \log \left(x + y\right)\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      12. lift-log.f64N/A

        \[\leadsto \left(\color{blue}{\log z} + \log \left(x + y\right)\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      13. lift-log.f64N/A

        \[\leadsto \left(\log z + \color{blue}{\log \left(x + y\right)}\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      14. lift-+.f64N/A

        \[\leadsto \left(\log z + \log \color{blue}{\left(x + y\right)}\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      15. +-commutativeN/A

        \[\leadsto \left(\log z + \log \color{blue}{\left(y + x\right)}\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      16. lift-+.f64N/A

        \[\leadsto \left(\log z + \log \color{blue}{\left(y + x\right)}\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      17. log-prodN/A

        \[\leadsto \color{blue}{\log \left(z \cdot \left(y + x\right)\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      18. lift-*.f64N/A

        \[\leadsto \log \color{blue}{\left(z \cdot \left(y + x\right)\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      19. lift-log.f64N/A

        \[\leadsto \color{blue}{\log \left(z \cdot \left(y + x\right)\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
    6. Applied rewrites80.3%

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

      \[\leadsto \color{blue}{\left(\log z + -1 \cdot \log \left(\frac{1}{y}\right)\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
    8. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\left(-1 \cdot \log \left(\frac{1}{y}\right) + \log z\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      2. mul-1-negN/A

        \[\leadsto \left(\color{blue}{\left(\mathsf{neg}\left(\log \left(\frac{1}{y}\right)\right)\right)} + \log z\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      3. log-recN/A

        \[\leadsto \left(\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right)\right) + \log z\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      4. remove-double-negN/A

        \[\leadsto \left(\color{blue}{\log y} + \log z\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      5. lower-+.f64N/A

        \[\leadsto \color{blue}{\left(\log y + \log z\right)} - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      6. lower-log.f64N/A

        \[\leadsto \left(\color{blue}{\log y} + \log z\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right) \]
      7. lower-log.f6471.2

        \[\leadsto \left(\log y + \color{blue}{\log z}\right) - \left(t - \left(a - 0.5\right) \cdot \log t\right) \]
    9. Applied rewrites71.2%

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

    Alternative 9: 69.9% accurate, 1.0× speedup?

    \[\begin{array}{l} \\ \mathsf{fma}\left(a - 0.5, \log t, \log z\right) - \left(t - \log y\right) \end{array} \]
    (FPCore (x y z t a)
     :precision binary64
     (- (fma (- a 0.5) (log t) (log z)) (- t (log y))))
    double code(double x, double y, double z, double t, double a) {
    	return fma((a - 0.5), log(t), log(z)) - (t - log(y));
    }
    
    function code(x, y, z, t, a)
    	return Float64(fma(Float64(a - 0.5), log(t), log(z)) - Float64(t - log(y)))
    end
    
    code[x_, y_, z_, t_, a_] := N[(N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - N[(t - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{fma}\left(a - 0.5, \log t, \log z\right) - \left(t - \log y\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. Taylor expanded in x around 0

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - \frac{1}{2}\right)\right)\right) - t} \]
    4. Step-by-step derivation
      1. associate--l+N/A

        \[\leadsto \color{blue}{\log y + \left(\left(\log z + \log t \cdot \left(a - \frac{1}{2}\right)\right) - t\right)} \]
      2. +-commutativeN/A

        \[\leadsto \color{blue}{\left(\left(\log z + \log t \cdot \left(a - \frac{1}{2}\right)\right) - t\right) + \log y} \]
      3. associate-+l-N/A

        \[\leadsto \color{blue}{\left(\log z + \log t \cdot \left(a - \frac{1}{2}\right)\right) - \left(t - \log y\right)} \]
      4. lower--.f64N/A

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

        \[\leadsto \color{blue}{\left(\log t \cdot \left(a - \frac{1}{2}\right) + \log z\right)} - \left(t - \log y\right) \]
      6. *-commutativeN/A

        \[\leadsto \left(\color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t} + \log z\right) - \left(t - \log y\right) \]
      7. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(a - \frac{1}{2}, \log t, \log z\right)} - \left(t - \log y\right) \]
      8. lower--.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{a - \frac{1}{2}}, \log t, \log z\right) - \left(t - \log y\right) \]
      9. lower-log.f64N/A

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \color{blue}{\log t}, \log z\right) - \left(t - \log y\right) \]
      10. lower-log.f64N/A

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \color{blue}{\log z}\right) - \left(t - \log y\right) \]
      11. lower--.f64N/A

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log z\right) - \color{blue}{\left(t - \log y\right)} \]
      12. lower-log.f6471.2

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log z\right) - \left(t - \color{blue}{\log y}\right) \]
    5. Applied rewrites71.2%

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

    Alternative 10: 64.4% accurate, 1.4× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -1.32 \cdot 10^{+51} \lor \neg \left(a \leq 3 \cdot 10^{+56}\right):\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + -0.5 \cdot \log t\\ \end{array} \end{array} \]
    (FPCore (x y z t a)
     :precision binary64
     (if (or (<= a -1.32e+51) (not (<= a 3e+56)))
       (* (log t) a)
       (+ (pow (/ -1.0 t) -1.0) (* -0.5 (log t)))))
    double code(double x, double y, double z, double t, double a) {
    	double tmp;
    	if ((a <= -1.32e+51) || !(a <= 3e+56)) {
    		tmp = log(t) * a;
    	} else {
    		tmp = pow((-1.0 / t), -1.0) + (-0.5 * log(t));
    	}
    	return tmp;
    }
    
    real(8) function code(x, y, z, t, a)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        real(8), intent (in) :: z
        real(8), intent (in) :: t
        real(8), intent (in) :: a
        real(8) :: tmp
        if ((a <= (-1.32d+51)) .or. (.not. (a <= 3d+56))) then
            tmp = log(t) * a
        else
            tmp = (((-1.0d0) / t) ** (-1.0d0)) + ((-0.5d0) * log(t))
        end if
        code = tmp
    end function
    
    public static double code(double x, double y, double z, double t, double a) {
    	double tmp;
    	if ((a <= -1.32e+51) || !(a <= 3e+56)) {
    		tmp = Math.log(t) * a;
    	} else {
    		tmp = Math.pow((-1.0 / t), -1.0) + (-0.5 * Math.log(t));
    	}
    	return tmp;
    }
    
    def code(x, y, z, t, a):
    	tmp = 0
    	if (a <= -1.32e+51) or not (a <= 3e+56):
    		tmp = math.log(t) * a
    	else:
    		tmp = math.pow((-1.0 / t), -1.0) + (-0.5 * math.log(t))
    	return tmp
    
    function code(x, y, z, t, a)
    	tmp = 0.0
    	if ((a <= -1.32e+51) || !(a <= 3e+56))
    		tmp = Float64(log(t) * a);
    	else
    		tmp = Float64((Float64(-1.0 / t) ^ -1.0) + Float64(-0.5 * log(t)));
    	end
    	return tmp
    end
    
    function tmp_2 = code(x, y, z, t, a)
    	tmp = 0.0;
    	if ((a <= -1.32e+51) || ~((a <= 3e+56)))
    		tmp = log(t) * a;
    	else
    		tmp = ((-1.0 / t) ^ -1.0) + (-0.5 * log(t));
    	end
    	tmp_2 = tmp;
    end
    
    code[x_, y_, z_, t_, a_] := If[Or[LessEqual[a, -1.32e+51], N[Not[LessEqual[a, 3e+56]], $MachinePrecision]], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision], N[(N[Power[N[(-1.0 / t), $MachinePrecision], -1.0], $MachinePrecision] + N[(-0.5 * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;a \leq -1.32 \cdot 10^{+51} \lor \neg \left(a \leq 3 \cdot 10^{+56}\right):\\
    \;\;\;\;\log t \cdot a\\
    
    \mathbf{else}:\\
    \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + -0.5 \cdot \log t\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if a < -1.32e51 or 3.00000000000000006e56 < a

      1. Initial program 99.6%

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

        \[\leadsto \color{blue}{a \cdot \log t} \]
      4. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto \color{blue}{\log t \cdot a} \]
        2. lower-*.f64N/A

          \[\leadsto \color{blue}{\log t \cdot a} \]
        3. lower-log.f6476.8

          \[\leadsto \color{blue}{\log t} \cdot a \]
      5. Applied rewrites76.8%

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

      if -1.32e51 < a < 3.00000000000000006e56

      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. Step-by-step derivation
        1. lift--.f64N/A

          \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        2. flip--N/A

          \[\leadsto \color{blue}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        3. clear-numN/A

          \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        4. lower-/.f64N/A

          \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        5. clear-numN/A

          \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        6. flip--N/A

          \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        7. lift--.f64N/A

          \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
        8. lower-/.f6499.5

          \[\leadsto \frac{1}{\color{blue}{\frac{1}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - 0.5\right) \cdot \log t \]
      4. Applied rewrites76.8%

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

        \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      6. Step-by-step derivation
        1. lower-/.f6461.8

          \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]
      7. Applied rewrites61.8%

        \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]
      8. Taylor expanded in a around 0

        \[\leadsto \frac{1}{\frac{-1}{t}} + \color{blue}{\frac{-1}{2} \cdot \log t} \]
      9. Step-by-step derivation
        1. lower-*.f64N/A

          \[\leadsto \frac{1}{\frac{-1}{t}} + \color{blue}{\frac{-1}{2} \cdot \log t} \]
        2. lower-log.f6456.2

          \[\leadsto \frac{1}{\frac{-1}{t}} + -0.5 \cdot \color{blue}{\log t} \]
      10. Applied rewrites56.2%

        \[\leadsto \frac{1}{\frac{-1}{t}} + \color{blue}{-0.5 \cdot \log t} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification64.4%

      \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -1.32 \cdot 10^{+51} \lor \neg \left(a \leq 3 \cdot 10^{+56}\right):\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;{\left(\frac{-1}{t}\right)}^{-1} + -0.5 \cdot \log t\\ \end{array} \]
    5. Add Preprocessing

    Alternative 11: 77.0% accurate, 1.4× speedup?

    \[\begin{array}{l} \\ {\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t \end{array} \]
    (FPCore (x y z t a)
     :precision binary64
     (+ (pow (/ -1.0 t) -1.0) (* (- a 0.5) (log t))))
    double code(double x, double y, double z, double t, double a) {
    	return pow((-1.0 / t), -1.0) + ((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 = (((-1.0d0) / t) ** (-1.0d0)) + ((a - 0.5d0) * log(t))
    end function
    
    public static double code(double x, double y, double z, double t, double a) {
    	return Math.pow((-1.0 / t), -1.0) + ((a - 0.5) * Math.log(t));
    }
    
    def code(x, y, z, t, a):
    	return math.pow((-1.0 / t), -1.0) + ((a - 0.5) * math.log(t))
    
    function code(x, y, z, t, a)
    	return Float64((Float64(-1.0 / t) ^ -1.0) + Float64(Float64(a - 0.5) * log(t)))
    end
    
    function tmp = code(x, y, z, t, a)
    	tmp = ((-1.0 / t) ^ -1.0) + ((a - 0.5) * log(t));
    end
    
    code[x_, y_, z_, t_, a_] := N[(N[Power[N[(-1.0 / t), $MachinePrecision], -1.0], $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    {\left(\frac{-1}{t}\right)}^{-1} + \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. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right)} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      2. flip--N/A

        \[\leadsto \color{blue}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      3. clear-numN/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) + t}{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      5. clear-numN/A

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t}{\left(\log \left(x + y\right) + \log z\right) + t}}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      6. flip--N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      7. lift--.f64N/A

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
      8. lower-/.f6499.5

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\left(\log \left(x + y\right) + \log z\right) - t}}} + \left(a - 0.5\right) \cdot \log t \]
    4. Applied rewrites80.2%

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

      \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - \frac{1}{2}\right) \cdot \log t \]
    6. Step-by-step derivation
      1. lower-/.f6476.8

        \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]
    7. Applied rewrites76.8%

      \[\leadsto \frac{1}{\color{blue}{\frac{-1}{t}}} + \left(a - 0.5\right) \cdot \log t \]
    8. Final simplification76.8%

      \[\leadsto {\left(\frac{-1}{t}\right)}^{-1} + \left(a - 0.5\right) \cdot \log t \]
    9. Add Preprocessing

    Alternative 12: 61.7% accurate, 2.7× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -4.3 \cdot 10^{+43} \lor \neg \left(a \leq 3 \cdot 10^{+56}\right):\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
    (FPCore (x y z t a)
     :precision binary64
     (if (or (<= a -4.3e+43) (not (<= a 3e+56))) (* (log t) a) (- t)))
    double code(double x, double y, double z, double t, double a) {
    	double tmp;
    	if ((a <= -4.3e+43) || !(a <= 3e+56)) {
    		tmp = log(t) * a;
    	} else {
    		tmp = -t;
    	}
    	return tmp;
    }
    
    real(8) function code(x, y, z, t, a)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        real(8), intent (in) :: z
        real(8), intent (in) :: t
        real(8), intent (in) :: a
        real(8) :: tmp
        if ((a <= (-4.3d+43)) .or. (.not. (a <= 3d+56))) then
            tmp = log(t) * a
        else
            tmp = -t
        end if
        code = tmp
    end function
    
    public static double code(double x, double y, double z, double t, double a) {
    	double tmp;
    	if ((a <= -4.3e+43) || !(a <= 3e+56)) {
    		tmp = Math.log(t) * a;
    	} else {
    		tmp = -t;
    	}
    	return tmp;
    }
    
    def code(x, y, z, t, a):
    	tmp = 0
    	if (a <= -4.3e+43) or not (a <= 3e+56):
    		tmp = math.log(t) * a
    	else:
    		tmp = -t
    	return tmp
    
    function code(x, y, z, t, a)
    	tmp = 0.0
    	if ((a <= -4.3e+43) || !(a <= 3e+56))
    		tmp = Float64(log(t) * a);
    	else
    		tmp = Float64(-t);
    	end
    	return tmp
    end
    
    function tmp_2 = code(x, y, z, t, a)
    	tmp = 0.0;
    	if ((a <= -4.3e+43) || ~((a <= 3e+56)))
    		tmp = log(t) * a;
    	else
    		tmp = -t;
    	end
    	tmp_2 = tmp;
    end
    
    code[x_, y_, z_, t_, a_] := If[Or[LessEqual[a, -4.3e+43], N[Not[LessEqual[a, 3e+56]], $MachinePrecision]], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision], (-t)]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;a \leq -4.3 \cdot 10^{+43} \lor \neg \left(a \leq 3 \cdot 10^{+56}\right):\\
    \;\;\;\;\log t \cdot a\\
    
    \mathbf{else}:\\
    \;\;\;\;-t\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if a < -4.3e43 or 3.00000000000000006e56 < a

      1. Initial program 99.6%

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

        \[\leadsto \color{blue}{a \cdot \log t} \]
      4. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto \color{blue}{\log t \cdot a} \]
        2. lower-*.f64N/A

          \[\leadsto \color{blue}{\log t \cdot a} \]
        3. lower-log.f6476.4

          \[\leadsto \color{blue}{\log t} \cdot a \]
      5. Applied rewrites76.4%

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

      if -4.3e43 < a < 3.00000000000000006e56

      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. Taylor expanded in t around inf

        \[\leadsto \color{blue}{-1 \cdot t} \]
      4. Step-by-step derivation
        1. mul-1-negN/A

          \[\leadsto \color{blue}{\mathsf{neg}\left(t\right)} \]
        2. lower-neg.f6450.4

          \[\leadsto \color{blue}{-t} \]
      5. Applied rewrites50.4%

        \[\leadsto \color{blue}{-t} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification60.9%

      \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -4.3 \cdot 10^{+43} \lor \neg \left(a \leq 3 \cdot 10^{+56}\right):\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]
    5. Add Preprocessing

    Alternative 13: 38.1% accurate, 107.0× 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. Add Preprocessing
    3. Taylor expanded in t around inf

      \[\leadsto \color{blue}{-1 \cdot t} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(t\right)} \]
      2. lower-neg.f6439.5

        \[\leadsto \color{blue}{-t} \]
    5. Applied rewrites39.5%

      \[\leadsto \color{blue}{-t} \]
    6. Add Preprocessing

    Developer Target 1: 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 2024315 
    (FPCore (x y z t a)
      :name "Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2"
      :precision binary64
    
      :alt
      (! :herbie-platform default (+ (log (+ x y)) (+ (- (log z) t) (* (- a 1/2) (log t)))))
    
      (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))