Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 19.5s
Alternatives: 14
Speedup: N/A×

Specification

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

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

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 14 alternatives:

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

Initial Program: 99.6% accurate, 1.0× speedup?

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

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

Alternative 1: 99.6% accurate, 1.0× speedup?

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

\\
\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t
\end{array}
Derivation
  1. Initial program 99.7%

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

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

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

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

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

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

Alternative 2: 81.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 0.00275:\\ \;\;\;\;\log z + \left(\log y + \log t \cdot \left(a - 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 0.00275)
   (+ (log z) (+ (log y) (* (log t) (- a 0.5))))
   (- (* (+ a -0.5) (log t)) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 0.00275) {
		tmp = log(z) + (log(y) + (log(t) * (a - 0.5)));
	} else {
		tmp = ((a + -0.5) * log(t)) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 0.00275d0) then
        tmp = log(z) + (log(y) + (log(t) * (a - 0.5d0)))
    else
        tmp = ((a + (-0.5d0)) * log(t)) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 0.00275) {
		tmp = Math.log(z) + (Math.log(y) + (Math.log(t) * (a - 0.5)));
	} else {
		tmp = ((a + -0.5) * Math.log(t)) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 0.00275:
		tmp = math.log(z) + (math.log(y) + (math.log(t) * (a - 0.5)))
	else:
		tmp = ((a + -0.5) * math.log(t)) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 0.00275)
		tmp = Float64(log(z) + Float64(log(y) + Float64(log(t) * Float64(a - 0.5))));
	else
		tmp = Float64(Float64(Float64(a + -0.5) * log(t)) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 0.00275)
		tmp = log(z) + (log(y) + (log(t) * (a - 0.5)));
	else
		tmp = ((a + -0.5) * log(t)) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 0.00275], N[(N[Log[z], $MachinePrecision] + N[(N[Log[y], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 0.00275:\\
\;\;\;\;\log z + \left(\log y + \log t \cdot \left(a - 0.5\right)\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 0.0027499999999999998

    1. Initial program 99.6%

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\log z - t\right) + \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right)} \]
    4. Taylor expanded in x around 0 70.9%

      \[\leadsto \left(\log z - t\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log y\right)} \]
    5. Taylor expanded in t around 0 69.7%

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

    if 0.0027499999999999998 < t

    1. Initial program 99.8%

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

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

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Taylor expanded in x around 0 70.3%

      \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) - t\right)} + \left(a + -0.5\right) \cdot \log t \]
    5. Step-by-step derivation
      1. associate--l+70.3%

        \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    6. Simplified70.3%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    7. Taylor expanded in t around inf 98.3%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a + -0.5\right) \cdot \log t \]
    8. Step-by-step derivation
      1. neg-mul-198.3%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a + -0.5\right) \cdot \log t \]
    9. Simplified98.3%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a + -0.5\right) \cdot \log t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification85.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 0.00275:\\ \;\;\;\;\log z + \left(\log y + \log t \cdot \left(a - 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\ \end{array} \]

Alternative 3: 81.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(a + -0.5\right) \cdot \log t\\ \mathbf{if}\;t \leq 0.00275:\\ \;\;\;\;t_1 + \left(\log z + \log y\right)\\ \mathbf{else}:\\ \;\;\;\;t_1 - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (* (+ a -0.5) (log t))))
   (if (<= t 0.00275) (+ t_1 (+ (log z) (log y))) (- t_1 t))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = (a + -0.5) * log(t);
	double tmp;
	if (t <= 0.00275) {
		tmp = t_1 + (log(z) + log(y));
	} else {
		tmp = t_1 - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: t_1
    real(8) :: tmp
    t_1 = (a + (-0.5d0)) * log(t)
    if (t <= 0.00275d0) then
        tmp = t_1 + (log(z) + log(y))
    else
        tmp = t_1 - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = (a + -0.5) * Math.log(t);
	double tmp;
	if (t <= 0.00275) {
		tmp = t_1 + (Math.log(z) + Math.log(y));
	} else {
		tmp = t_1 - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = (a + -0.5) * math.log(t)
	tmp = 0
	if t <= 0.00275:
		tmp = t_1 + (math.log(z) + math.log(y))
	else:
		tmp = t_1 - t
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(Float64(a + -0.5) * log(t))
	tmp = 0.0
	if (t <= 0.00275)
		tmp = Float64(t_1 + Float64(log(z) + log(y)));
	else
		tmp = Float64(t_1 - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = (a + -0.5) * log(t);
	tmp = 0.0;
	if (t <= 0.00275)
		tmp = t_1 + (log(z) + log(y));
	else
		tmp = t_1 - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t, 0.00275], N[(t$95$1 + N[(N[Log[z], $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(t$95$1 - t), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(a + -0.5\right) \cdot \log t\\
\mathbf{if}\;t \leq 0.00275:\\
\;\;\;\;t_1 + \left(\log z + \log y\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 0.0027499999999999998

    1. Initial program 99.6%

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

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

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Taylor expanded in x around 0 70.9%

      \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) - t\right)} + \left(a + -0.5\right) \cdot \log t \]
    5. Step-by-step derivation
      1. associate--l+70.9%

        \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    6. Simplified70.9%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    7. Taylor expanded in t around 0 69.7%

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

    if 0.0027499999999999998 < t

    1. Initial program 99.8%

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

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

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Taylor expanded in x around 0 70.3%

      \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) - t\right)} + \left(a + -0.5\right) \cdot \log t \]
    5. Step-by-step derivation
      1. associate--l+70.3%

        \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    6. Simplified70.3%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    7. Taylor expanded in t around inf 98.3%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a + -0.5\right) \cdot \log t \]
    8. Step-by-step derivation
      1. neg-mul-198.3%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a + -0.5\right) \cdot \log t \]
    9. Simplified98.3%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a + -0.5\right) \cdot \log t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification85.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 0.00275:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \left(\log z + \log y\right)\\ \mathbf{else}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\ \end{array} \]

Alternative 4: 68.8% accurate, 1.0× speedup?

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

\\
\left(a + -0.5\right) \cdot \log t + \left(\log z + \left(\log y - t\right)\right)
\end{array}
Derivation
  1. Initial program 99.7%

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

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

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

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

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

    \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) - t\right)} + \left(a + -0.5\right) \cdot \log t \]
  5. Step-by-step derivation
    1. associate--l+70.6%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
  6. Simplified70.6%

    \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
  7. Final simplification70.6%

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

Alternative 5: 80.7% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(a + -0.5\right) \cdot \log t\\ \mathbf{if}\;a \leq -2.35 \cdot 10^{-39}:\\ \;\;\;\;t_1 - t\\ \mathbf{elif}\;a \leq 1050:\\ \;\;\;\;\left(t_1 + \log \left(\left(x + y\right) \cdot z\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log y - t\right) + a \cdot \log t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (* (+ a -0.5) (log t))))
   (if (<= a -2.35e-39)
     (- t_1 t)
     (if (<= a 1050.0)
       (- (+ t_1 (log (* (+ x y) z))) t)
       (+ (- (log y) t) (* a (log t)))))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = (a + -0.5) * log(t);
	double tmp;
	if (a <= -2.35e-39) {
		tmp = t_1 - t;
	} else if (a <= 1050.0) {
		tmp = (t_1 + log(((x + y) * z))) - t;
	} else {
		tmp = (log(y) - t) + (a * log(t));
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: t_1
    real(8) :: tmp
    t_1 = (a + (-0.5d0)) * log(t)
    if (a <= (-2.35d-39)) then
        tmp = t_1 - t
    else if (a <= 1050.0d0) then
        tmp = (t_1 + log(((x + y) * z))) - t
    else
        tmp = (log(y) - t) + (a * log(t))
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = (a + -0.5) * Math.log(t);
	double tmp;
	if (a <= -2.35e-39) {
		tmp = t_1 - t;
	} else if (a <= 1050.0) {
		tmp = (t_1 + Math.log(((x + y) * z))) - t;
	} else {
		tmp = (Math.log(y) - t) + (a * Math.log(t));
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = (a + -0.5) * math.log(t)
	tmp = 0
	if a <= -2.35e-39:
		tmp = t_1 - t
	elif a <= 1050.0:
		tmp = (t_1 + math.log(((x + y) * z))) - t
	else:
		tmp = (math.log(y) - t) + (a * math.log(t))
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(Float64(a + -0.5) * log(t))
	tmp = 0.0
	if (a <= -2.35e-39)
		tmp = Float64(t_1 - t);
	elseif (a <= 1050.0)
		tmp = Float64(Float64(t_1 + log(Float64(Float64(x + y) * z))) - t);
	else
		tmp = Float64(Float64(log(y) - t) + Float64(a * log(t)));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = (a + -0.5) * log(t);
	tmp = 0.0;
	if (a <= -2.35e-39)
		tmp = t_1 - t;
	elseif (a <= 1050.0)
		tmp = (t_1 + log(((x + y) * z))) - t;
	else
		tmp = (log(y) - t) + (a * log(t));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[a, -2.35e-39], N[(t$95$1 - t), $MachinePrecision], If[LessEqual[a, 1050.0], N[(N[(t$95$1 + N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(a + -0.5\right) \cdot \log t\\
\mathbf{if}\;a \leq -2.35 \cdot 10^{-39}:\\
\;\;\;\;t_1 - t\\

\mathbf{elif}\;a \leq 1050:\\
\;\;\;\;\left(t_1 + \log \left(\left(x + y\right) \cdot z\right)\right) - t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if a < -2.3500000000000001e-39

    1. Initial program 99.7%

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

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

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Taylor expanded in x around 0 79.3%

      \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) - t\right)} + \left(a + -0.5\right) \cdot \log t \]
    5. Step-by-step derivation
      1. associate--l+79.3%

        \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    6. Simplified79.3%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    7. Taylor expanded in t around inf 93.9%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a + -0.5\right) \cdot \log t \]
    8. Step-by-step derivation
      1. neg-mul-193.9%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a + -0.5\right) \cdot \log t \]
    9. Simplified93.9%

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

    if -2.3500000000000001e-39 < a < 1050

    1. Initial program 99.8%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \color{blue}{\left(\left(a + -0.5\right) \cdot \log t + \left(\log \left(x + y\right) + \log z\right)\right) - t} \]
      7. sum-log79.1%

        \[\leadsto \left(\left(a + -0.5\right) \cdot \log t + \color{blue}{\log \left(\left(x + y\right) \cdot z\right)}\right) - t \]
    5. Applied egg-rr79.1%

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

    if 1050 < a

    1. Initial program 99.7%

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
    4. Taylor expanded in x around 0 73.7%

      \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z + \log y\right)\right) - t} \]
    5. Step-by-step derivation
      1. associate-+r+73.7%

        \[\leadsto \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \log y\right)} - t \]
      2. associate--l+73.7%

        \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \left(\log y - t\right)} \]
      3. fma-def73.7%

        \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} + \left(\log y - t\right) \]
      4. sub-neg73.7%

        \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) + \left(\log y - t\right) \]
      5. metadata-eval73.7%

        \[\leadsto \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) + \left(\log y - t\right) \]
      6. +-commutative73.7%

        \[\leadsto \mathsf{fma}\left(\color{blue}{-0.5 + a}, \log t, \log z\right) + \left(\log y - t\right) \]
    6. Simplified73.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
    7. Taylor expanded in a around inf 73.3%

      \[\leadsto \color{blue}{a \cdot \log t} + \left(\log y - t\right) \]
    8. Step-by-step derivation
      1. *-commutative73.3%

        \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
    9. Simplified73.3%

      \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
  3. Recombined 3 regimes into one program.
  4. Final simplification82.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -2.35 \cdot 10^{-39}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\ \mathbf{elif}\;a \leq 1050:\\ \;\;\;\;\left(\left(a + -0.5\right) \cdot \log t + \log \left(\left(x + y\right) \cdot z\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log y - t\right) + a \cdot \log t\\ \end{array} \]

Alternative 6: 58.8% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(z \cdot \left(y \cdot {t}^{-0.5}\right)\right) - t\\ t_2 := \left(\log y - t\right) + a \cdot \log t\\ \mathbf{if}\;a \leq -1.65 \cdot 10^{-56}:\\ \;\;\;\;t_2\\ \mathbf{elif}\;a \leq 1.08 \cdot 10^{-189}:\\ \;\;\;\;t_1\\ \mathbf{elif}\;a \leq 2.45 \cdot 10^{-144}:\\ \;\;\;\;\log \left(x + y\right) - t\\ \mathbf{elif}\;a \leq 1.7 \cdot 10^{-17}:\\ \;\;\;\;t_1\\ \mathbf{else}:\\ \;\;\;\;t_2\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (- (log (* z (* y (pow t -0.5)))) t))
        (t_2 (+ (- (log y) t) (* a (log t)))))
   (if (<= a -1.65e-56)
     t_2
     (if (<= a 1.08e-189)
       t_1
       (if (<= a 2.45e-144)
         (- (log (+ x y)) t)
         (if (<= a 1.7e-17) t_1 t_2))))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = log((z * (y * pow(t, -0.5)))) - t;
	double t_2 = (log(y) - t) + (a * log(t));
	double tmp;
	if (a <= -1.65e-56) {
		tmp = t_2;
	} else if (a <= 1.08e-189) {
		tmp = t_1;
	} else if (a <= 2.45e-144) {
		tmp = log((x + y)) - t;
	} else if (a <= 1.7e-17) {
		tmp = t_1;
	} else {
		tmp = 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((z * (y * (t ** (-0.5d0))))) - t
    t_2 = (log(y) - t) + (a * log(t))
    if (a <= (-1.65d-56)) then
        tmp = t_2
    else if (a <= 1.08d-189) then
        tmp = t_1
    else if (a <= 2.45d-144) then
        tmp = log((x + y)) - t
    else if (a <= 1.7d-17) then
        tmp = t_1
    else
        tmp = 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((z * (y * Math.pow(t, -0.5)))) - t;
	double t_2 = (Math.log(y) - t) + (a * Math.log(t));
	double tmp;
	if (a <= -1.65e-56) {
		tmp = t_2;
	} else if (a <= 1.08e-189) {
		tmp = t_1;
	} else if (a <= 2.45e-144) {
		tmp = Math.log((x + y)) - t;
	} else if (a <= 1.7e-17) {
		tmp = t_1;
	} else {
		tmp = t_2;
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = math.log((z * (y * math.pow(t, -0.5)))) - t
	t_2 = (math.log(y) - t) + (a * math.log(t))
	tmp = 0
	if a <= -1.65e-56:
		tmp = t_2
	elif a <= 1.08e-189:
		tmp = t_1
	elif a <= 2.45e-144:
		tmp = math.log((x + y)) - t
	elif a <= 1.7e-17:
		tmp = t_1
	else:
		tmp = t_2
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(log(Float64(z * Float64(y * (t ^ -0.5)))) - t)
	t_2 = Float64(Float64(log(y) - t) + Float64(a * log(t)))
	tmp = 0.0
	if (a <= -1.65e-56)
		tmp = t_2;
	elseif (a <= 1.08e-189)
		tmp = t_1;
	elseif (a <= 2.45e-144)
		tmp = Float64(log(Float64(x + y)) - t);
	elseif (a <= 1.7e-17)
		tmp = t_1;
	else
		tmp = t_2;
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = log((z * (y * (t ^ -0.5)))) - t;
	t_2 = (log(y) - t) + (a * log(t));
	tmp = 0.0;
	if (a <= -1.65e-56)
		tmp = t_2;
	elseif (a <= 1.08e-189)
		tmp = t_1;
	elseif (a <= 2.45e-144)
		tmp = log((x + y)) - t;
	elseif (a <= 1.7e-17)
		tmp = t_1;
	else
		tmp = t_2;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[N[(z * N[(y * N[Power[t, -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]}, Block[{t$95$2 = N[(N[(N[Log[y], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[a, -1.65e-56], t$95$2, If[LessEqual[a, 1.08e-189], t$95$1, If[LessEqual[a, 2.45e-144], N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision], If[LessEqual[a, 1.7e-17], t$95$1, t$95$2]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \log \left(z \cdot \left(y \cdot {t}^{-0.5}\right)\right) - t\\
t_2 := \left(\log y - t\right) + a \cdot \log t\\
\mathbf{if}\;a \leq -1.65 \cdot 10^{-56}:\\
\;\;\;\;t_2\\

\mathbf{elif}\;a \leq 1.08 \cdot 10^{-189}:\\
\;\;\;\;t_1\\

\mathbf{elif}\;a \leq 2.45 \cdot 10^{-144}:\\
\;\;\;\;\log \left(x + y\right) - t\\

\mathbf{elif}\;a \leq 1.7 \cdot 10^{-17}:\\
\;\;\;\;t_1\\

\mathbf{else}:\\
\;\;\;\;t_2\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if a < -1.64999999999999992e-56 or 1.6999999999999999e-17 < a

    1. Initial program 99.7%

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
    4. Taylor expanded in x around 0 75.2%

      \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z + \log y\right)\right) - t} \]
    5. Step-by-step derivation
      1. associate-+r+75.2%

        \[\leadsto \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \log y\right)} - t \]
      2. associate--l+75.2%

        \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \left(\log y - t\right)} \]
      3. fma-def75.3%

        \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} + \left(\log y - t\right) \]
      4. sub-neg75.3%

        \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) + \left(\log y - t\right) \]
      5. metadata-eval75.3%

        \[\leadsto \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) + \left(\log y - t\right) \]
      6. +-commutative75.3%

        \[\leadsto \mathsf{fma}\left(\color{blue}{-0.5 + a}, \log t, \log z\right) + \left(\log y - t\right) \]
    6. Simplified75.3%

      \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
    7. Taylor expanded in a around inf 72.7%

      \[\leadsto \color{blue}{a \cdot \log t} + \left(\log y - t\right) \]
    8. Step-by-step derivation
      1. *-commutative72.7%

        \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
    9. Simplified72.7%

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

    if -1.64999999999999992e-56 < a < 1.08e-189 or 2.45000000000000005e-144 < a < 1.6999999999999999e-17

    1. Initial program 99.8%

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z + \log y\right)\right) - t} \]
    5. Step-by-step derivation
      1. associate-+r+66.0%

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

        \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \left(\log y - t\right)} \]
      3. fma-def65.9%

        \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} + \left(\log y - t\right) \]
      4. sub-neg65.9%

        \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) + \left(\log y - t\right) \]
      5. metadata-eval65.9%

        \[\leadsto \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) + \left(\log y - t\right) \]
      6. +-commutative65.9%

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

      \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
    7. Taylor expanded in a around 0 66.0%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y + -0.5 \cdot \log t\right)\right) - t} \]
    8. Step-by-step derivation
      1. rem-log-exp52.3%

        \[\leadsto \color{blue}{\log \left(e^{\log z + \left(\log y + -0.5 \cdot \log t\right)}\right)} - t \]
      2. exp-sum52.3%

        \[\leadsto \log \color{blue}{\left(e^{\log z} \cdot e^{\log y + -0.5 \cdot \log t}\right)} - t \]
      3. rem-exp-log52.3%

        \[\leadsto \log \left(\color{blue}{z} \cdot e^{\log y + -0.5 \cdot \log t}\right) - t \]
      4. exp-sum52.4%

        \[\leadsto \log \left(z \cdot \color{blue}{\left(e^{\log y} \cdot e^{-0.5 \cdot \log t}\right)}\right) - t \]
      5. rem-exp-log52.7%

        \[\leadsto \log \left(z \cdot \left(\color{blue}{y} \cdot e^{-0.5 \cdot \log t}\right)\right) - t \]
      6. *-commutative52.7%

        \[\leadsto \log \left(z \cdot \left(y \cdot e^{\color{blue}{\log t \cdot -0.5}}\right)\right) - t \]
      7. exp-to-pow52.7%

        \[\leadsto \log \left(z \cdot \left(y \cdot \color{blue}{{t}^{-0.5}}\right)\right) - t \]
    9. Simplified52.7%

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

    if 1.08e-189 < a < 2.45000000000000005e-144

    1. Initial program 99.9%

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

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+100.0%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative100.0%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. fma-def100.0%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z - t\right)} \]
      5. remove-double-neg100.0%

        \[\leadsto \log \left(x + y\right) + \mathsf{fma}\left(\color{blue}{-\left(-\left(a - 0.5\right)\right)}, \log t, \log z - t\right) \]
      6. remove-double-neg100.0%

        \[\leadsto \log \left(x + y\right) + \mathsf{fma}\left(\color{blue}{a - 0.5}, \log t, \log z - t\right) \]
      7. sub-neg100.0%

        \[\leadsto \log \left(x + y\right) + \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z - t\right) \]
      8. metadata-eval100.0%

        \[\leadsto \log \left(x + y\right) + \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z - t\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
    4. Taylor expanded in t around inf 78.4%

      \[\leadsto \log \left(x + y\right) + \color{blue}{-1 \cdot t} \]
    5. Step-by-step derivation
      1. neg-mul-178.4%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(-t\right)} \]
    6. Simplified78.4%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(-t\right)} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification66.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -1.65 \cdot 10^{-56}:\\ \;\;\;\;\left(\log y - t\right) + a \cdot \log t\\ \mathbf{elif}\;a \leq 1.08 \cdot 10^{-189}:\\ \;\;\;\;\log \left(z \cdot \left(y \cdot {t}^{-0.5}\right)\right) - t\\ \mathbf{elif}\;a \leq 2.45 \cdot 10^{-144}:\\ \;\;\;\;\log \left(x + y\right) - t\\ \mathbf{elif}\;a \leq 1.7 \cdot 10^{-17}:\\ \;\;\;\;\log \left(z \cdot \left(y \cdot {t}^{-0.5}\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log y - t\right) + a \cdot \log t\\ \end{array} \]

Alternative 7: 80.1% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -2.8 \cdot 10^{-39}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\ \mathbf{elif}\;a \leq 4.4 \cdot 10^{-15}:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \left(-0.5 \cdot \log t - t\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y - t\right) + a \cdot \log t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= a -2.8e-39)
   (- (* (+ a -0.5) (log t)) t)
   (if (<= a 4.4e-15)
     (+ (log (* (+ x y) z)) (- (* -0.5 (log t)) t))
     (+ (- (log y) t) (* a (log t))))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (a <= -2.8e-39) {
		tmp = ((a + -0.5) * log(t)) - t;
	} else if (a <= 4.4e-15) {
		tmp = log(((x + y) * z)) + ((-0.5 * log(t)) - t);
	} else {
		tmp = (log(y) - t) + (a * log(t));
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (a <= (-2.8d-39)) then
        tmp = ((a + (-0.5d0)) * log(t)) - t
    else if (a <= 4.4d-15) then
        tmp = log(((x + y) * z)) + (((-0.5d0) * log(t)) - t)
    else
        tmp = (log(y) - t) + (a * log(t))
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (a <= -2.8e-39) {
		tmp = ((a + -0.5) * Math.log(t)) - t;
	} else if (a <= 4.4e-15) {
		tmp = Math.log(((x + y) * z)) + ((-0.5 * Math.log(t)) - t);
	} else {
		tmp = (Math.log(y) - t) + (a * Math.log(t));
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if a <= -2.8e-39:
		tmp = ((a + -0.5) * math.log(t)) - t
	elif a <= 4.4e-15:
		tmp = math.log(((x + y) * z)) + ((-0.5 * math.log(t)) - t)
	else:
		tmp = (math.log(y) - t) + (a * math.log(t))
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (a <= -2.8e-39)
		tmp = Float64(Float64(Float64(a + -0.5) * log(t)) - t);
	elseif (a <= 4.4e-15)
		tmp = Float64(log(Float64(Float64(x + y) * z)) + Float64(Float64(-0.5 * log(t)) - t));
	else
		tmp = Float64(Float64(log(y) - t) + Float64(a * log(t)));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (a <= -2.8e-39)
		tmp = ((a + -0.5) * log(t)) - t;
	elseif (a <= 4.4e-15)
		tmp = log(((x + y) * z)) + ((-0.5 * log(t)) - t);
	else
		tmp = (log(y) - t) + (a * log(t));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[a, -2.8e-39], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[a, 4.4e-15], N[(N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision] + N[(N[(-0.5 * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -2.8 \cdot 10^{-39}:\\
\;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\

\mathbf{elif}\;a \leq 4.4 \cdot 10^{-15}:\\
\;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \left(-0.5 \cdot \log t - t\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if a < -2.8000000000000001e-39

    1. Initial program 99.7%

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

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

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Taylor expanded in x around 0 79.3%

      \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) - t\right)} + \left(a + -0.5\right) \cdot \log t \]
    5. Step-by-step derivation
      1. associate--l+79.3%

        \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    6. Simplified79.3%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    7. Taylor expanded in t around inf 93.9%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a + -0.5\right) \cdot \log t \]
    8. Step-by-step derivation
      1. neg-mul-193.9%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a + -0.5\right) \cdot \log t \]
    9. Simplified93.9%

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

    if -2.8000000000000001e-39 < a < 4.39999999999999971e-15

    1. Initial program 99.8%

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
    4. Taylor expanded in a around 0 99.8%

      \[\leadsto \color{blue}{\left(\log \left(y + x\right) + \left(\log z + -0.5 \cdot \log t\right)\right) - t} \]
    5. Step-by-step derivation
      1. associate-+r+99.8%

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

        \[\leadsto \left(\left(\log \color{blue}{\left(x + y\right)} + \log z\right) + -0.5 \cdot \log t\right) - t \]
      3. log-prod79.3%

        \[\leadsto \left(\color{blue}{\log \left(\left(x + y\right) \cdot z\right)} + -0.5 \cdot \log t\right) - t \]
      4. associate--l+79.2%

        \[\leadsto \color{blue}{\log \left(\left(x + y\right) \cdot z\right) + \left(-0.5 \cdot \log t - t\right)} \]
      5. *-commutative79.2%

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

        \[\leadsto \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) + \left(-0.5 \cdot \log t - t\right) \]
    6. Simplified79.2%

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

    if 4.39999999999999971e-15 < a

    1. Initial program 99.7%

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
    4. Taylor expanded in x around 0 71.3%

      \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z + \log y\right)\right) - t} \]
    5. Step-by-step derivation
      1. associate-+r+71.3%

        \[\leadsto \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \log y\right)} - t \]
      2. associate--l+71.3%

        \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \left(\log y - t\right)} \]
      3. fma-def71.3%

        \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} + \left(\log y - t\right) \]
      4. sub-neg71.3%

        \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) + \left(\log y - t\right) \]
      5. metadata-eval71.3%

        \[\leadsto \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) + \left(\log y - t\right) \]
      6. +-commutative71.3%

        \[\leadsto \mathsf{fma}\left(\color{blue}{-0.5 + a}, \log t, \log z\right) + \left(\log y - t\right) \]
    6. Simplified71.3%

      \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
    7. Taylor expanded in a around inf 69.8%

      \[\leadsto \color{blue}{a \cdot \log t} + \left(\log y - t\right) \]
    8. Step-by-step derivation
      1. *-commutative69.8%

        \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
    9. Simplified69.8%

      \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
  3. Recombined 3 regimes into one program.
  4. Final simplification81.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -2.8 \cdot 10^{-39}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\ \mathbf{elif}\;a \leq 4.4 \cdot 10^{-15}:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \left(-0.5 \cdot \log t - t\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y - t\right) + a \cdot \log t\\ \end{array} \]

Alternative 8: 80.1% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -7.5 \cdot 10^{-40}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\ \mathbf{elif}\;a \leq 5 \cdot 10^{-15}:\\ \;\;\;\;\left(\log \left(\left(x + y\right) \cdot z\right) + -0.5 \cdot \log t\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log y - t\right) + a \cdot \log t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= a -7.5e-40)
   (- (* (+ a -0.5) (log t)) t)
   (if (<= a 5e-15)
     (- (+ (log (* (+ x y) z)) (* -0.5 (log t))) t)
     (+ (- (log y) t) (* a (log t))))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (a <= -7.5e-40) {
		tmp = ((a + -0.5) * log(t)) - t;
	} else if (a <= 5e-15) {
		tmp = (log(((x + y) * z)) + (-0.5 * log(t))) - t;
	} else {
		tmp = (log(y) - t) + (a * log(t));
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (a <= (-7.5d-40)) then
        tmp = ((a + (-0.5d0)) * log(t)) - t
    else if (a <= 5d-15) then
        tmp = (log(((x + y) * z)) + ((-0.5d0) * log(t))) - t
    else
        tmp = (log(y) - t) + (a * log(t))
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (a <= -7.5e-40) {
		tmp = ((a + -0.5) * Math.log(t)) - t;
	} else if (a <= 5e-15) {
		tmp = (Math.log(((x + y) * z)) + (-0.5 * Math.log(t))) - t;
	} else {
		tmp = (Math.log(y) - t) + (a * Math.log(t));
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if a <= -7.5e-40:
		tmp = ((a + -0.5) * math.log(t)) - t
	elif a <= 5e-15:
		tmp = (math.log(((x + y) * z)) + (-0.5 * math.log(t))) - t
	else:
		tmp = (math.log(y) - t) + (a * math.log(t))
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (a <= -7.5e-40)
		tmp = Float64(Float64(Float64(a + -0.5) * log(t)) - t);
	elseif (a <= 5e-15)
		tmp = Float64(Float64(log(Float64(Float64(x + y) * z)) + Float64(-0.5 * log(t))) - t);
	else
		tmp = Float64(Float64(log(y) - t) + Float64(a * log(t)));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (a <= -7.5e-40)
		tmp = ((a + -0.5) * log(t)) - t;
	elseif (a <= 5e-15)
		tmp = (log(((x + y) * z)) + (-0.5 * log(t))) - t;
	else
		tmp = (log(y) - t) + (a * log(t));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[a, -7.5e-40], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[a, 5e-15], N[(N[(N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision] + N[(-0.5 * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -7.5 \cdot 10^{-40}:\\
\;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\

\mathbf{elif}\;a \leq 5 \cdot 10^{-15}:\\
\;\;\;\;\left(\log \left(\left(x + y\right) \cdot z\right) + -0.5 \cdot \log t\right) - t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if a < -7.50000000000000069e-40

    1. Initial program 99.7%

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

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

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Taylor expanded in x around 0 79.3%

      \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) - t\right)} + \left(a + -0.5\right) \cdot \log t \]
    5. Step-by-step derivation
      1. associate--l+79.3%

        \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    6. Simplified79.3%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    7. Taylor expanded in t around inf 93.9%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a + -0.5\right) \cdot \log t \]
    8. Step-by-step derivation
      1. neg-mul-193.9%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a + -0.5\right) \cdot \log t \]
    9. Simplified93.9%

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

    if -7.50000000000000069e-40 < a < 4.99999999999999999e-15

    1. Initial program 99.8%

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
    4. Taylor expanded in a around 0 99.8%

      \[\leadsto \color{blue}{\left(\log \left(y + x\right) + \left(\log z + -0.5 \cdot \log t\right)\right) - t} \]
    5. Step-by-step derivation
      1. associate-+r+99.8%

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

        \[\leadsto \left(\left(\log \color{blue}{\left(x + y\right)} + \log z\right) + -0.5 \cdot \log t\right) - t \]
      3. log-prod79.3%

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

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

        \[\leadsto \left(\log \left(z \cdot \color{blue}{\left(y + x\right)}\right) + -0.5 \cdot \log t\right) - t \]
    6. Simplified79.3%

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

    if 4.99999999999999999e-15 < a

    1. Initial program 99.7%

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
    4. Taylor expanded in x around 0 71.3%

      \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z + \log y\right)\right) - t} \]
    5. Step-by-step derivation
      1. associate-+r+71.3%

        \[\leadsto \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \log y\right)} - t \]
      2. associate--l+71.3%

        \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \left(\log y - t\right)} \]
      3. fma-def71.3%

        \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} + \left(\log y - t\right) \]
      4. sub-neg71.3%

        \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) + \left(\log y - t\right) \]
      5. metadata-eval71.3%

        \[\leadsto \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) + \left(\log y - t\right) \]
      6. +-commutative71.3%

        \[\leadsto \mathsf{fma}\left(\color{blue}{-0.5 + a}, \log t, \log z\right) + \left(\log y - t\right) \]
    6. Simplified71.3%

      \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
    7. Taylor expanded in a around inf 69.8%

      \[\leadsto \color{blue}{a \cdot \log t} + \left(\log y - t\right) \]
    8. Step-by-step derivation
      1. *-commutative69.8%

        \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
    9. Simplified69.8%

      \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
  3. Recombined 3 regimes into one program.
  4. Final simplification81.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -7.5 \cdot 10^{-40}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\ \mathbf{elif}\;a \leq 5 \cdot 10^{-15}:\\ \;\;\;\;\left(\log \left(\left(x + y\right) \cdot z\right) + -0.5 \cdot \log t\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log y - t\right) + a \cdot \log t\\ \end{array} \]

Alternative 9: 67.6% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -1.1 \cdot 10^{-40}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\ \mathbf{elif}\;a \leq 1.75 \cdot 10^{-15}:\\ \;\;\;\;\left(-0.5 \cdot \log t + \log \left(y \cdot z\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log y - t\right) + a \cdot \log t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= a -1.1e-40)
   (- (* (+ a -0.5) (log t)) t)
   (if (<= a 1.75e-15)
     (- (+ (* -0.5 (log t)) (log (* y z))) t)
     (+ (- (log y) t) (* a (log t))))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (a <= -1.1e-40) {
		tmp = ((a + -0.5) * log(t)) - t;
	} else if (a <= 1.75e-15) {
		tmp = ((-0.5 * log(t)) + log((y * z))) - t;
	} else {
		tmp = (log(y) - t) + (a * log(t));
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (a <= (-1.1d-40)) then
        tmp = ((a + (-0.5d0)) * log(t)) - t
    else if (a <= 1.75d-15) then
        tmp = (((-0.5d0) * log(t)) + log((y * z))) - t
    else
        tmp = (log(y) - t) + (a * log(t))
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (a <= -1.1e-40) {
		tmp = ((a + -0.5) * Math.log(t)) - t;
	} else if (a <= 1.75e-15) {
		tmp = ((-0.5 * Math.log(t)) + Math.log((y * z))) - t;
	} else {
		tmp = (Math.log(y) - t) + (a * Math.log(t));
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if a <= -1.1e-40:
		tmp = ((a + -0.5) * math.log(t)) - t
	elif a <= 1.75e-15:
		tmp = ((-0.5 * math.log(t)) + math.log((y * z))) - t
	else:
		tmp = (math.log(y) - t) + (a * math.log(t))
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (a <= -1.1e-40)
		tmp = Float64(Float64(Float64(a + -0.5) * log(t)) - t);
	elseif (a <= 1.75e-15)
		tmp = Float64(Float64(Float64(-0.5 * log(t)) + log(Float64(y * z))) - t);
	else
		tmp = Float64(Float64(log(y) - t) + Float64(a * log(t)));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (a <= -1.1e-40)
		tmp = ((a + -0.5) * log(t)) - t;
	elseif (a <= 1.75e-15)
		tmp = ((-0.5 * log(t)) + log((y * z))) - t;
	else
		tmp = (log(y) - t) + (a * log(t));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[a, -1.1e-40], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[a, 1.75e-15], N[(N[(N[(-0.5 * N[Log[t], $MachinePrecision]), $MachinePrecision] + N[Log[N[(y * z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -1.1 \cdot 10^{-40}:\\
\;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\

\mathbf{elif}\;a \leq 1.75 \cdot 10^{-15}:\\
\;\;\;\;\left(-0.5 \cdot \log t + \log \left(y \cdot z\right)\right) - t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if a < -1.10000000000000004e-40

    1. Initial program 99.7%

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

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

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

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

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right) + \left(a + -0.5\right) \cdot \log t} \]
    4. Taylor expanded in x around 0 79.3%

      \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) - t\right)} + \left(a + -0.5\right) \cdot \log t \]
    5. Step-by-step derivation
      1. associate--l+79.3%

        \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    6. Simplified79.3%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    7. Taylor expanded in t around inf 93.9%

      \[\leadsto \color{blue}{-1 \cdot t} + \left(a + -0.5\right) \cdot \log t \]
    8. Step-by-step derivation
      1. neg-mul-193.9%

        \[\leadsto \color{blue}{\left(-t\right)} + \left(a + -0.5\right) \cdot \log t \]
    9. Simplified93.9%

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

    if -1.10000000000000004e-40 < a < 1.75e-15

    1. Initial program 99.8%

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) - t\right)} + \left(a + -0.5\right) \cdot \log t \]
    5. Step-by-step derivation
      1. associate--l+62.7%

        \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    6. Simplified62.7%

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

      \[\leadsto \color{blue}{\left(\log z + \left(\log y + -0.5 \cdot \log t\right)\right) - t} \]
    8. Step-by-step derivation
      1. associate-+r+62.7%

        \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) + -0.5 \cdot \log t\right)} - t \]
      2. log-prod54.5%

        \[\leadsto \left(\color{blue}{\log \left(z \cdot y\right)} + -0.5 \cdot \log t\right) - t \]
      3. *-commutative54.5%

        \[\leadsto \left(\log \left(z \cdot y\right) + \color{blue}{\log t \cdot -0.5}\right) - t \]
    9. Simplified54.5%

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

    if 1.75e-15 < a

    1. Initial program 99.7%

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
    4. Taylor expanded in x around 0 71.3%

      \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z + \log y\right)\right) - t} \]
    5. Step-by-step derivation
      1. associate-+r+71.3%

        \[\leadsto \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \log y\right)} - t \]
      2. associate--l+71.3%

        \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \left(\log y - t\right)} \]
      3. fma-def71.3%

        \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} + \left(\log y - t\right) \]
      4. sub-neg71.3%

        \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) + \left(\log y - t\right) \]
      5. metadata-eval71.3%

        \[\leadsto \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) + \left(\log y - t\right) \]
      6. +-commutative71.3%

        \[\leadsto \mathsf{fma}\left(\color{blue}{-0.5 + a}, \log t, \log z\right) + \left(\log y - t\right) \]
    6. Simplified71.3%

      \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
    7. Taylor expanded in a around inf 69.8%

      \[\leadsto \color{blue}{a \cdot \log t} + \left(\log y - t\right) \]
    8. Step-by-step derivation
      1. *-commutative69.8%

        \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
    9. Simplified69.8%

      \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
  3. Recombined 3 regimes into one program.
  4. Final simplification71.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -1.1 \cdot 10^{-40}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t - t\\ \mathbf{elif}\;a \leq 1.75 \cdot 10^{-15}:\\ \;\;\;\;\left(-0.5 \cdot \log t + \log \left(y \cdot z\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log y - t\right) + a \cdot \log t\\ \end{array} \]

Alternative 10: 60.8% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 2.7 \cdot 10^{-72}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \log \left(y \cdot z\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y - t\right) + a \cdot \log t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 2.7e-72)
   (+ (* (+ a -0.5) (log t)) (log (* y z)))
   (+ (- (log y) t) (* a (log t)))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 2.7e-72) {
		tmp = ((a + -0.5) * log(t)) + log((y * z));
	} else {
		tmp = (log(y) - t) + (a * log(t));
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 2.7d-72) then
        tmp = ((a + (-0.5d0)) * log(t)) + log((y * z))
    else
        tmp = (log(y) - t) + (a * log(t))
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 2.7e-72) {
		tmp = ((a + -0.5) * Math.log(t)) + Math.log((y * z));
	} else {
		tmp = (Math.log(y) - t) + (a * Math.log(t));
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 2.7e-72:
		tmp = ((a + -0.5) * math.log(t)) + math.log((y * z))
	else:
		tmp = (math.log(y) - t) + (a * math.log(t))
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 2.7e-72)
		tmp = Float64(Float64(Float64(a + -0.5) * log(t)) + log(Float64(y * z)));
	else
		tmp = Float64(Float64(log(y) - t) + Float64(a * log(t)));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 2.7e-72)
		tmp = ((a + -0.5) * log(t)) + log((y * z));
	else
		tmp = (log(y) - t) + (a * log(t));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 2.7e-72], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] + N[Log[N[(y * z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 2.7 \cdot 10^{-72}:\\
\;\;\;\;\left(a + -0.5\right) \cdot \log t + \log \left(y \cdot z\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 2.7e-72

    1. Initial program 99.7%

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) - t\right)} + \left(a + -0.5\right) \cdot \log t \]
    5. Step-by-step derivation
      1. associate--l+71.9%

        \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    6. Simplified71.9%

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

      \[\leadsto \color{blue}{\left(\log z + \log y\right)} + \left(a + -0.5\right) \cdot \log t \]
    8. Step-by-step derivation
      1. log-prod57.7%

        \[\leadsto \color{blue}{\log \left(z \cdot y\right)} + \left(a + -0.5\right) \cdot \log t \]
    9. Simplified57.7%

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

    if 2.7e-72 < t

    1. Initial program 99.7%

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
    4. Taylor expanded in x around 0 69.9%

      \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z + \log y\right)\right) - t} \]
    5. Step-by-step derivation
      1. associate-+r+69.9%

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

        \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \left(\log y - t\right)} \]
      3. fma-def69.9%

        \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} + \left(\log y - t\right) \]
      4. sub-neg69.9%

        \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) + \left(\log y - t\right) \]
      5. metadata-eval69.9%

        \[\leadsto \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) + \left(\log y - t\right) \]
      6. +-commutative69.9%

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

      \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
    7. Taylor expanded in a around inf 64.9%

      \[\leadsto \color{blue}{a \cdot \log t} + \left(\log y - t\right) \]
    8. Step-by-step derivation
      1. *-commutative64.9%

        \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
    9. Simplified64.9%

      \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification62.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 2.7 \cdot 10^{-72}:\\ \;\;\;\;\left(a + -0.5\right) \cdot \log t + \log \left(y \cdot z\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y - t\right) + a \cdot \log t\\ \end{array} \]

Alternative 11: 57.5% accurate, 1.5× speedup?

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

\\
\left(\log y - t\right) + a \cdot \log t
\end{array}
Derivation
  1. Initial program 99.7%

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

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

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

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

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

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

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

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

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

    \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
  4. Taylor expanded in x around 0 70.6%

    \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z + \log y\right)\right) - t} \]
  5. Step-by-step derivation
    1. associate-+r+70.6%

      \[\leadsto \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \log y\right)} - t \]
    2. associate--l+70.6%

      \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \left(\log y - t\right)} \]
    3. fma-def70.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} + \left(\log y - t\right) \]
    4. sub-neg70.6%

      \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) + \left(\log y - t\right) \]
    5. metadata-eval70.6%

      \[\leadsto \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) + \left(\log y - t\right) \]
    6. +-commutative70.6%

      \[\leadsto \mathsf{fma}\left(\color{blue}{-0.5 + a}, \log t, \log z\right) + \left(\log y - t\right) \]
  6. Simplified70.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
  7. Taylor expanded in a around inf 60.2%

    \[\leadsto \color{blue}{a \cdot \log t} + \left(\log y - t\right) \]
  8. Step-by-step derivation
    1. *-commutative60.2%

      \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
  9. Simplified60.2%

    \[\leadsto \color{blue}{\log t \cdot a} + \left(\log y - t\right) \]
  10. Final simplification60.2%

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

Alternative 12: 77.3% accurate, 2.9× speedup?

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

\\
\left(a + -0.5\right) \cdot \log t - t
\end{array}
Derivation
  1. Initial program 99.7%

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

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

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

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

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

    \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) - t\right)} + \left(a + -0.5\right) \cdot \log t \]
  5. Step-by-step derivation
    1. associate--l+70.6%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
  6. Simplified70.6%

    \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
  7. Taylor expanded in t around inf 80.7%

    \[\leadsto \color{blue}{-1 \cdot t} + \left(a + -0.5\right) \cdot \log t \]
  8. Step-by-step derivation
    1. neg-mul-180.7%

      \[\leadsto \color{blue}{\left(-t\right)} + \left(a + -0.5\right) \cdot \log t \]
  9. Simplified80.7%

    \[\leadsto \color{blue}{\left(-t\right)} + \left(a + -0.5\right) \cdot \log t \]
  10. Final simplification80.7%

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

Alternative 13: 63.2% accurate, 3.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 7.6 \cdot 10^{+27}:\\ \;\;\;\;a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 7.6e+27) (* a (log t)) (- t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 7.6e+27) {
		tmp = a * log(t);
	} else {
		tmp = -t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 7.6d+27) then
        tmp = a * log(t)
    else
        tmp = -t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 7.6e+27) {
		tmp = a * Math.log(t);
	} else {
		tmp = -t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 7.6e+27:
		tmp = a * math.log(t)
	else:
		tmp = -t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 7.6e+27)
		tmp = Float64(a * log(t));
	else
		tmp = Float64(-t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 7.6e+27)
		tmp = a * log(t);
	else
		tmp = -t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 7.6e+27], N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision], (-t)]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 7.6 \cdot 10^{+27}:\\
\;\;\;\;a \cdot \log t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 7.60000000000000043e27

    1. Initial program 99.6%

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\left(\log z + \log y\right) - t\right)} + \left(a + -0.5\right) \cdot \log t \]
    5. Step-by-step derivation
      1. associate--l+70.5%

        \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    6. Simplified70.5%

      \[\leadsto \color{blue}{\left(\log z + \left(\log y - t\right)\right)} + \left(a + -0.5\right) \cdot \log t \]
    7. Taylor expanded in a around inf 54.9%

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

    if 7.60000000000000043e27 < t

    1. Initial program 99.9%

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
    4. Taylor expanded in x around 0 70.6%

      \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z + \log y\right)\right) - t} \]
    5. Step-by-step derivation
      1. associate-+r+70.6%

        \[\leadsto \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \log y\right)} - t \]
      2. associate--l+70.6%

        \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \left(\log y - t\right)} \]
      3. fma-def70.6%

        \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} + \left(\log y - t\right) \]
      4. sub-neg70.6%

        \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) + \left(\log y - t\right) \]
      5. metadata-eval70.6%

        \[\leadsto \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) + \left(\log y - t\right) \]
      6. +-commutative70.6%

        \[\leadsto \mathsf{fma}\left(\color{blue}{-0.5 + a}, \log t, \log z\right) + \left(\log y - t\right) \]
    6. Simplified70.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
    7. Taylor expanded in t around inf 75.2%

      \[\leadsto \color{blue}{-1 \cdot t} \]
    8. Step-by-step derivation
      1. neg-mul-175.2%

        \[\leadsto \color{blue}{-t} \]
    9. Simplified75.2%

      \[\leadsto \color{blue}{-t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification64.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 7.6 \cdot 10^{+27}:\\ \;\;\;\;a \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]

Alternative 14: 38.1% accurate, 156.5× speedup?

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

\\
-t
\end{array}
Derivation
  1. Initial program 99.7%

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

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

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

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

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

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

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

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

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

    \[\leadsto \color{blue}{\log \left(x + y\right) + \mathsf{fma}\left(a + -0.5, \log t, \log z - t\right)} \]
  4. Taylor expanded in x around 0 70.6%

    \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z + \log y\right)\right) - t} \]
  5. Step-by-step derivation
    1. associate-+r+70.6%

      \[\leadsto \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \log y\right)} - t \]
    2. associate--l+70.6%

      \[\leadsto \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \log z\right) + \left(\log y - t\right)} \]
    3. fma-def70.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} + \left(\log y - t\right) \]
    4. sub-neg70.6%

      \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) + \left(\log y - t\right) \]
    5. metadata-eval70.6%

      \[\leadsto \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) + \left(\log y - t\right) \]
    6. +-commutative70.6%

      \[\leadsto \mathsf{fma}\left(\color{blue}{-0.5 + a}, \log t, \log z\right) + \left(\log y - t\right) \]
  6. Simplified70.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
  7. Taylor expanded in t around inf 39.5%

    \[\leadsto \color{blue}{-1 \cdot t} \]
  8. Step-by-step derivation
    1. neg-mul-139.5%

      \[\leadsto \color{blue}{-t} \]
  9. Simplified39.5%

    \[\leadsto \color{blue}{-t} \]
  10. Final simplification39.5%

    \[\leadsto -t \]

Developer target: 99.6% accurate, 1.0× speedup?

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

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

Reproduce

?
herbie shell --seed 2023240 
(FPCore (x y z t a)
  :name "Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2"
  :precision binary64

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

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