SynthBasics:moogVCF from YampaSynth-0.2

Percentage Accurate: 93.4% → 96.2%
Time: 8.1s
Alternatives: 8
Speedup: 1.0×

Specification

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

\\
x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right)
\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 8 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: 93.4% accurate, 1.0× speedup?

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

\\
x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right)
\end{array}

Alternative 1: 96.2% accurate, 1.0× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;y\_m \leq 1.5 \cdot 10^{+153}:\\ \;\;\;\;x + \left(y\_m \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y\_m}\right) - \tanh \left(\frac{x}{y\_m}\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(z, t - x, x\right)\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z t)
 :precision binary64
 (if (<= y_m 1.5e+153)
   (+ x (* (* y_m z) (- (tanh (/ t y_m)) (tanh (/ x y_m)))))
   (fma z (- t x) x)))
y_m = fabs(y);
double code(double x, double y_m, double z, double t) {
	double tmp;
	if (y_m <= 1.5e+153) {
		tmp = x + ((y_m * z) * (tanh((t / y_m)) - tanh((x / y_m))));
	} else {
		tmp = fma(z, (t - x), x);
	}
	return tmp;
}
y_m = abs(y)
function code(x, y_m, z, t)
	tmp = 0.0
	if (y_m <= 1.5e+153)
		tmp = Float64(x + Float64(Float64(y_m * z) * Float64(tanh(Float64(t / y_m)) - tanh(Float64(x / y_m)))));
	else
		tmp = fma(z, Float64(t - x), x);
	end
	return tmp
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_, t_] := If[LessEqual[y$95$m, 1.5e+153], N[(x + N[(N[(y$95$m * z), $MachinePrecision] * N[(N[Tanh[N[(t / y$95$m), $MachinePrecision]], $MachinePrecision] - N[Tanh[N[(x / y$95$m), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(z * N[(t - x), $MachinePrecision] + x), $MachinePrecision]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;y\_m \leq 1.5 \cdot 10^{+153}:\\
\;\;\;\;x + \left(y\_m \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y\_m}\right) - \tanh \left(\frac{x}{y\_m}\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(z, t - x, x\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < 1.50000000000000009e153

    1. Initial program 97.3%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing

    if 1.50000000000000009e153 < y

    1. Initial program 62.0%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in y around inf 97.6%

      \[\leadsto \color{blue}{x + z \cdot \left(t - x\right)} \]
    4. Step-by-step derivation
      1. +-commutative97.6%

        \[\leadsto \color{blue}{z \cdot \left(t - x\right) + x} \]
      2. fma-define97.7%

        \[\leadsto \color{blue}{\mathsf{fma}\left(z, t - x, x\right)} \]
    5. Simplified97.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(z, t - x, x\right)} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 2: 85.8% accurate, 1.9× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;y\_m \leq 6 \cdot 10^{+126}:\\ \;\;\;\;x + y\_m \cdot \left(z \cdot \tanh \left(\frac{t}{y\_m}\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(z, t - x, x\right)\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z t)
 :precision binary64
 (if (<= y_m 6e+126) (+ x (* y_m (* z (tanh (/ t y_m))))) (fma z (- t x) x)))
y_m = fabs(y);
double code(double x, double y_m, double z, double t) {
	double tmp;
	if (y_m <= 6e+126) {
		tmp = x + (y_m * (z * tanh((t / y_m))));
	} else {
		tmp = fma(z, (t - x), x);
	}
	return tmp;
}
y_m = abs(y)
function code(x, y_m, z, t)
	tmp = 0.0
	if (y_m <= 6e+126)
		tmp = Float64(x + Float64(y_m * Float64(z * tanh(Float64(t / y_m)))));
	else
		tmp = fma(z, Float64(t - x), x);
	end
	return tmp
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_, t_] := If[LessEqual[y$95$m, 6e+126], N[(x + N[(y$95$m * N[(z * N[Tanh[N[(t / y$95$m), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(z * N[(t - x), $MachinePrecision] + x), $MachinePrecision]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;y\_m \leq 6 \cdot 10^{+126}:\\
\;\;\;\;x + y\_m \cdot \left(z \cdot \tanh \left(\frac{t}{y\_m}\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(z, t - x, x\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < 6.0000000000000005e126

    1. Initial program 97.3%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 27.8%

      \[\leadsto x + \color{blue}{y \cdot \left(z \cdot \left(\frac{e^{\frac{t}{y}}}{e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}} - \frac{1}{e^{\frac{t}{y}} \cdot \left(e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}\right)}\right)\right)} \]
    4. Step-by-step derivation
      1. associate-/r*27.8%

        \[\leadsto x + y \cdot \left(z \cdot \left(\frac{e^{\frac{t}{y}}}{e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}} - \color{blue}{\frac{\frac{1}{e^{\frac{t}{y}}}}{e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}}}\right)\right) \]
      2. rec-exp27.9%

        \[\leadsto x + y \cdot \left(z \cdot \left(\frac{e^{\frac{t}{y}}}{e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}} - \frac{\color{blue}{e^{-\frac{t}{y}}}}{e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}}\right)\right) \]
      3. div-sub27.9%

        \[\leadsto x + y \cdot \left(z \cdot \color{blue}{\frac{e^{\frac{t}{y}} - e^{-\frac{t}{y}}}{e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}}}\right) \]
      4. rec-exp27.9%

        \[\leadsto x + y \cdot \left(z \cdot \frac{e^{\frac{t}{y}} - e^{-\frac{t}{y}}}{e^{\frac{t}{y}} + \color{blue}{e^{-\frac{t}{y}}}}\right) \]
      5. tanh-def-a82.5%

        \[\leadsto x + y \cdot \left(z \cdot \color{blue}{\tanh \left(\frac{t}{y}\right)}\right) \]
    5. Simplified82.5%

      \[\leadsto x + \color{blue}{y \cdot \left(z \cdot \tanh \left(\frac{t}{y}\right)\right)} \]

    if 6.0000000000000005e126 < y

    1. Initial program 63.9%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in y around inf 97.7%

      \[\leadsto \color{blue}{x + z \cdot \left(t - x\right)} \]
    4. Step-by-step derivation
      1. +-commutative97.7%

        \[\leadsto \color{blue}{z \cdot \left(t - x\right) + x} \]
      2. fma-define97.8%

        \[\leadsto \color{blue}{\mathsf{fma}\left(z, t - x, x\right)} \]
    5. Simplified97.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(z, t - x, x\right)} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 3: 78.1% accurate, 1.9× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;y\_m \leq 1.38 \cdot 10^{+17}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(z, t - x, x\right)\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z t)
 :precision binary64
 (if (<= y_m 1.38e+17) x (fma z (- t x) x)))
y_m = fabs(y);
double code(double x, double y_m, double z, double t) {
	double tmp;
	if (y_m <= 1.38e+17) {
		tmp = x;
	} else {
		tmp = fma(z, (t - x), x);
	}
	return tmp;
}
y_m = abs(y)
function code(x, y_m, z, t)
	tmp = 0.0
	if (y_m <= 1.38e+17)
		tmp = x;
	else
		tmp = fma(z, Float64(t - x), x);
	end
	return tmp
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_, t_] := If[LessEqual[y$95$m, 1.38e+17], x, N[(z * N[(t - x), $MachinePrecision] + x), $MachinePrecision]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;y\_m \leq 1.38 \cdot 10^{+17}:\\
\;\;\;\;x\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(z, t - x, x\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < 1.38e17

    1. Initial program 97.0%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf 67.6%

      \[\leadsto \color{blue}{x} \]

    if 1.38e17 < y

    1. Initial program 74.6%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in y around inf 89.8%

      \[\leadsto \color{blue}{x + z \cdot \left(t - x\right)} \]
    4. Step-by-step derivation
      1. +-commutative89.8%

        \[\leadsto \color{blue}{z \cdot \left(t - x\right) + x} \]
      2. fma-define89.8%

        \[\leadsto \color{blue}{\mathsf{fma}\left(z, t - x, x\right)} \]
    5. Simplified89.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(z, t - x, x\right)} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 4: 70.5% accurate, 10.6× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;y\_m \leq 1.55 \cdot 10^{+17}:\\ \;\;\;\;x\\ \mathbf{elif}\;y\_m \leq 1.5 \cdot 10^{+263} \lor \neg \left(y\_m \leq 8.5 \cdot 10^{+280}\right):\\ \;\;\;\;x + z \cdot t\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(1 - z\right)\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z t)
 :precision binary64
 (if (<= y_m 1.55e+17)
   x
   (if (or (<= y_m 1.5e+263) (not (<= y_m 8.5e+280)))
     (+ x (* z t))
     (* x (- 1.0 z)))))
y_m = fabs(y);
double code(double x, double y_m, double z, double t) {
	double tmp;
	if (y_m <= 1.55e+17) {
		tmp = x;
	} else if ((y_m <= 1.5e+263) || !(y_m <= 8.5e+280)) {
		tmp = x + (z * t);
	} else {
		tmp = x * (1.0 - z);
	}
	return tmp;
}
y_m = abs(y)
real(8) function code(x, y_m, z, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: y_m
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8) :: tmp
    if (y_m <= 1.55d+17) then
        tmp = x
    else if ((y_m <= 1.5d+263) .or. (.not. (y_m <= 8.5d+280))) then
        tmp = x + (z * t)
    else
        tmp = x * (1.0d0 - z)
    end if
    code = tmp
end function
y_m = Math.abs(y);
public static double code(double x, double y_m, double z, double t) {
	double tmp;
	if (y_m <= 1.55e+17) {
		tmp = x;
	} else if ((y_m <= 1.5e+263) || !(y_m <= 8.5e+280)) {
		tmp = x + (z * t);
	} else {
		tmp = x * (1.0 - z);
	}
	return tmp;
}
y_m = math.fabs(y)
def code(x, y_m, z, t):
	tmp = 0
	if y_m <= 1.55e+17:
		tmp = x
	elif (y_m <= 1.5e+263) or not (y_m <= 8.5e+280):
		tmp = x + (z * t)
	else:
		tmp = x * (1.0 - z)
	return tmp
y_m = abs(y)
function code(x, y_m, z, t)
	tmp = 0.0
	if (y_m <= 1.55e+17)
		tmp = x;
	elseif ((y_m <= 1.5e+263) || !(y_m <= 8.5e+280))
		tmp = Float64(x + Float64(z * t));
	else
		tmp = Float64(x * Float64(1.0 - z));
	end
	return tmp
end
y_m = abs(y);
function tmp_2 = code(x, y_m, z, t)
	tmp = 0.0;
	if (y_m <= 1.55e+17)
		tmp = x;
	elseif ((y_m <= 1.5e+263) || ~((y_m <= 8.5e+280)))
		tmp = x + (z * t);
	else
		tmp = x * (1.0 - z);
	end
	tmp_2 = tmp;
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_, t_] := If[LessEqual[y$95$m, 1.55e+17], x, If[Or[LessEqual[y$95$m, 1.5e+263], N[Not[LessEqual[y$95$m, 8.5e+280]], $MachinePrecision]], N[(x + N[(z * t), $MachinePrecision]), $MachinePrecision], N[(x * N[(1.0 - z), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;y\_m \leq 1.55 \cdot 10^{+17}:\\
\;\;\;\;x\\

\mathbf{elif}\;y\_m \leq 1.5 \cdot 10^{+263} \lor \neg \left(y\_m \leq 8.5 \cdot 10^{+280}\right):\\
\;\;\;\;x + z \cdot t\\

\mathbf{else}:\\
\;\;\;\;x \cdot \left(1 - z\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < 1.55e17

    1. Initial program 97.0%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf 67.6%

      \[\leadsto \color{blue}{x} \]

    if 1.55e17 < y < 1.49999999999999995e263 or 8.50000000000000028e280 < y

    1. Initial program 73.6%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 29.8%

      \[\leadsto x + \color{blue}{y \cdot \left(z \cdot \left(\frac{e^{\frac{t}{y}}}{e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}} - \frac{1}{e^{\frac{t}{y}} \cdot \left(e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}\right)}\right)\right)} \]
    4. Step-by-step derivation
      1. associate-/r*29.8%

        \[\leadsto x + y \cdot \left(z \cdot \left(\frac{e^{\frac{t}{y}}}{e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}} - \color{blue}{\frac{\frac{1}{e^{\frac{t}{y}}}}{e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}}}\right)\right) \]
      2. rec-exp29.8%

        \[\leadsto x + y \cdot \left(z \cdot \left(\frac{e^{\frac{t}{y}}}{e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}} - \frac{\color{blue}{e^{-\frac{t}{y}}}}{e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}}\right)\right) \]
      3. div-sub29.8%

        \[\leadsto x + y \cdot \left(z \cdot \color{blue}{\frac{e^{\frac{t}{y}} - e^{-\frac{t}{y}}}{e^{\frac{t}{y}} + \frac{1}{e^{\frac{t}{y}}}}}\right) \]
      4. rec-exp29.8%

        \[\leadsto x + y \cdot \left(z \cdot \frac{e^{\frac{t}{y}} - e^{-\frac{t}{y}}}{e^{\frac{t}{y}} + \color{blue}{e^{-\frac{t}{y}}}}\right) \]
      5. tanh-def-a67.5%

        \[\leadsto x + y \cdot \left(z \cdot \color{blue}{\tanh \left(\frac{t}{y}\right)}\right) \]
    5. Simplified67.5%

      \[\leadsto x + \color{blue}{y \cdot \left(z \cdot \tanh \left(\frac{t}{y}\right)\right)} \]
    6. Taylor expanded in y around inf 73.7%

      \[\leadsto x + \color{blue}{t \cdot z} \]
    7. Step-by-step derivation
      1. *-commutative73.7%

        \[\leadsto x + \color{blue}{z \cdot t} \]
    8. Simplified73.7%

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

    if 1.49999999999999995e263 < y < 8.50000000000000028e280

    1. Initial program 83.6%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in y around inf 100.0%

      \[\leadsto x + \color{blue}{z \cdot \left(t - x\right)} \]
    4. Taylor expanded in x around inf 100.0%

      \[\leadsto \color{blue}{x \cdot \left(1 + -1 \cdot z\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg100.0%

        \[\leadsto x \cdot \left(1 + \color{blue}{\left(-z\right)}\right) \]
      2. unsub-neg100.0%

        \[\leadsto x \cdot \color{blue}{\left(1 - z\right)} \]
    6. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(1 - z\right)} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification69.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq 1.55 \cdot 10^{+17}:\\ \;\;\;\;x\\ \mathbf{elif}\;y \leq 1.5 \cdot 10^{+263} \lor \neg \left(y \leq 8.5 \cdot 10^{+280}\right):\\ \;\;\;\;x + z \cdot t\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(1 - z\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 78.1% accurate, 17.7× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;y\_m \leq 4.9 \cdot 10^{+17}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x + z \cdot \left(t - x\right)\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z t)
 :precision binary64
 (if (<= y_m 4.9e+17) x (+ x (* z (- t x)))))
y_m = fabs(y);
double code(double x, double y_m, double z, double t) {
	double tmp;
	if (y_m <= 4.9e+17) {
		tmp = x;
	} else {
		tmp = x + (z * (t - x));
	}
	return tmp;
}
y_m = abs(y)
real(8) function code(x, y_m, z, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: y_m
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8) :: tmp
    if (y_m <= 4.9d+17) then
        tmp = x
    else
        tmp = x + (z * (t - x))
    end if
    code = tmp
end function
y_m = Math.abs(y);
public static double code(double x, double y_m, double z, double t) {
	double tmp;
	if (y_m <= 4.9e+17) {
		tmp = x;
	} else {
		tmp = x + (z * (t - x));
	}
	return tmp;
}
y_m = math.fabs(y)
def code(x, y_m, z, t):
	tmp = 0
	if y_m <= 4.9e+17:
		tmp = x
	else:
		tmp = x + (z * (t - x))
	return tmp
y_m = abs(y)
function code(x, y_m, z, t)
	tmp = 0.0
	if (y_m <= 4.9e+17)
		tmp = x;
	else
		tmp = Float64(x + Float64(z * Float64(t - x)));
	end
	return tmp
end
y_m = abs(y);
function tmp_2 = code(x, y_m, z, t)
	tmp = 0.0;
	if (y_m <= 4.9e+17)
		tmp = x;
	else
		tmp = x + (z * (t - x));
	end
	tmp_2 = tmp;
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_, t_] := If[LessEqual[y$95$m, 4.9e+17], x, N[(x + N[(z * N[(t - x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;y\_m \leq 4.9 \cdot 10^{+17}:\\
\;\;\;\;x\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < 4.9e17

    1. Initial program 97.0%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf 67.6%

      \[\leadsto \color{blue}{x} \]

    if 4.9e17 < y

    1. Initial program 74.6%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in y around inf 89.8%

      \[\leadsto x + \color{blue}{z \cdot \left(t - x\right)} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 6: 67.4% accurate, 21.3× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;y\_m \leq 5800000000000:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(1 - z\right)\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z t)
 :precision binary64
 (if (<= y_m 5800000000000.0) x (* x (- 1.0 z))))
y_m = fabs(y);
double code(double x, double y_m, double z, double t) {
	double tmp;
	if (y_m <= 5800000000000.0) {
		tmp = x;
	} else {
		tmp = x * (1.0 - z);
	}
	return tmp;
}
y_m = abs(y)
real(8) function code(x, y_m, z, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: y_m
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8) :: tmp
    if (y_m <= 5800000000000.0d0) then
        tmp = x
    else
        tmp = x * (1.0d0 - z)
    end if
    code = tmp
end function
y_m = Math.abs(y);
public static double code(double x, double y_m, double z, double t) {
	double tmp;
	if (y_m <= 5800000000000.0) {
		tmp = x;
	} else {
		tmp = x * (1.0 - z);
	}
	return tmp;
}
y_m = math.fabs(y)
def code(x, y_m, z, t):
	tmp = 0
	if y_m <= 5800000000000.0:
		tmp = x
	else:
		tmp = x * (1.0 - z)
	return tmp
y_m = abs(y)
function code(x, y_m, z, t)
	tmp = 0.0
	if (y_m <= 5800000000000.0)
		tmp = x;
	else
		tmp = Float64(x * Float64(1.0 - z));
	end
	return tmp
end
y_m = abs(y);
function tmp_2 = code(x, y_m, z, t)
	tmp = 0.0;
	if (y_m <= 5800000000000.0)
		tmp = x;
	else
		tmp = x * (1.0 - z);
	end
	tmp_2 = tmp;
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_, t_] := If[LessEqual[y$95$m, 5800000000000.0], x, N[(x * N[(1.0 - z), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;y\_m \leq 5800000000000:\\
\;\;\;\;x\\

\mathbf{else}:\\
\;\;\;\;x \cdot \left(1 - z\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < 5.8e12

    1. Initial program 97.0%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf 67.6%

      \[\leadsto \color{blue}{x} \]

    if 5.8e12 < y

    1. Initial program 74.6%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in y around inf 89.8%

      \[\leadsto x + \color{blue}{z \cdot \left(t - x\right)} \]
    4. Taylor expanded in x around inf 52.5%

      \[\leadsto \color{blue}{x \cdot \left(1 + -1 \cdot z\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg52.5%

        \[\leadsto x \cdot \left(1 + \color{blue}{\left(-z\right)}\right) \]
      2. unsub-neg52.5%

        \[\leadsto x \cdot \color{blue}{\left(1 - z\right)} \]
    6. Simplified52.5%

      \[\leadsto \color{blue}{x \cdot \left(1 - z\right)} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 7: 60.6% accurate, 23.6× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;z \leq -4.5 \cdot 10^{+213}:\\ \;\;\;\;x \cdot \left(-z\right)\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z t) :precision binary64 (if (<= z -4.5e+213) (* x (- z)) x))
y_m = fabs(y);
double code(double x, double y_m, double z, double t) {
	double tmp;
	if (z <= -4.5e+213) {
		tmp = x * -z;
	} else {
		tmp = x;
	}
	return tmp;
}
y_m = abs(y)
real(8) function code(x, y_m, z, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: y_m
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8) :: tmp
    if (z <= (-4.5d+213)) then
        tmp = x * -z
    else
        tmp = x
    end if
    code = tmp
end function
y_m = Math.abs(y);
public static double code(double x, double y_m, double z, double t) {
	double tmp;
	if (z <= -4.5e+213) {
		tmp = x * -z;
	} else {
		tmp = x;
	}
	return tmp;
}
y_m = math.fabs(y)
def code(x, y_m, z, t):
	tmp = 0
	if z <= -4.5e+213:
		tmp = x * -z
	else:
		tmp = x
	return tmp
y_m = abs(y)
function code(x, y_m, z, t)
	tmp = 0.0
	if (z <= -4.5e+213)
		tmp = Float64(x * Float64(-z));
	else
		tmp = x;
	end
	return tmp
end
y_m = abs(y);
function tmp_2 = code(x, y_m, z, t)
	tmp = 0.0;
	if (z <= -4.5e+213)
		tmp = x * -z;
	else
		tmp = x;
	end
	tmp_2 = tmp;
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_, t_] := If[LessEqual[z, -4.5e+213], N[(x * (-z)), $MachinePrecision], x]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;z \leq -4.5 \cdot 10^{+213}:\\
\;\;\;\;x \cdot \left(-z\right)\\

\mathbf{else}:\\
\;\;\;\;x\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -4.5000000000000002e213

    1. Initial program 86.8%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in y around inf 66.7%

      \[\leadsto x + \color{blue}{z \cdot \left(t - x\right)} \]
    4. Taylor expanded in x around inf 37.6%

      \[\leadsto \color{blue}{x \cdot \left(1 + -1 \cdot z\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg37.6%

        \[\leadsto x \cdot \left(1 + \color{blue}{\left(-z\right)}\right) \]
      2. unsub-neg37.6%

        \[\leadsto x \cdot \color{blue}{\left(1 - z\right)} \]
    6. Simplified37.6%

      \[\leadsto \color{blue}{x \cdot \left(1 - z\right)} \]
    7. Taylor expanded in z around inf 37.6%

      \[\leadsto \color{blue}{-1 \cdot \left(x \cdot z\right)} \]
    8. Step-by-step derivation
      1. mul-1-neg37.6%

        \[\leadsto \color{blue}{-x \cdot z} \]
      2. *-commutative37.6%

        \[\leadsto -\color{blue}{z \cdot x} \]
      3. distribute-rgt-neg-in37.6%

        \[\leadsto \color{blue}{z \cdot \left(-x\right)} \]
    9. Simplified37.6%

      \[\leadsto \color{blue}{z \cdot \left(-x\right)} \]

    if -4.5000000000000002e213 < z

    1. Initial program 92.6%

      \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf 64.7%

      \[\leadsto \color{blue}{x} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification62.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -4.5 \cdot 10^{+213}:\\ \;\;\;\;x \cdot \left(-z\right)\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 60.7% accurate, 213.0× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ x \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z t) :precision binary64 x)
y_m = fabs(y);
double code(double x, double y_m, double z, double t) {
	return x;
}
y_m = abs(y)
real(8) function code(x, y_m, z, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: y_m
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    code = x
end function
y_m = Math.abs(y);
public static double code(double x, double y_m, double z, double t) {
	return x;
}
y_m = math.fabs(y)
def code(x, y_m, z, t):
	return x
y_m = abs(y)
function code(x, y_m, z, t)
	return x
end
y_m = abs(y);
function tmp = code(x, y_m, z, t)
	tmp = x;
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_, t_] := x
\begin{array}{l}
y_m = \left|y\right|

\\
x
\end{array}
Derivation
  1. Initial program 92.0%

    \[x + \left(y \cdot z\right) \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right) \]
  2. Add Preprocessing
  3. Taylor expanded in x around inf 59.6%

    \[\leadsto \color{blue}{x} \]
  4. Add Preprocessing

Developer target: 97.2% accurate, 1.0× speedup?

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

\\
x + y \cdot \left(z \cdot \left(\tanh \left(\frac{t}{y}\right) - \tanh \left(\frac{x}{y}\right)\right)\right)
\end{array}

Reproduce

?
herbie shell --seed 2024096 
(FPCore (x y z t)
  :name "SynthBasics:moogVCF from YampaSynth-0.2"
  :precision binary64

  :alt
  (+ x (* y (* z (- (tanh (/ t y)) (tanh (/ x y))))))

  (+ x (* (* y z) (- (tanh (/ t y)) (tanh (/ x y))))))