
(FPCore (x y z) :precision binary64 (+ x (/ y (- (* 1.1283791670955126 (exp z)) (* x y)))))
double code(double x, double y, double z) {
return x + (y / ((1.1283791670955126 * exp(z)) - (x * y)));
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = x + (y / ((1.1283791670955126d0 * exp(z)) - (x * y)))
end function
public static double code(double x, double y, double z) {
return x + (y / ((1.1283791670955126 * Math.exp(z)) - (x * y)));
}
def code(x, y, z): return x + (y / ((1.1283791670955126 * math.exp(z)) - (x * y)))
function code(x, y, z) return Float64(x + Float64(y / Float64(Float64(1.1283791670955126 * exp(z)) - Float64(x * y)))) end
function tmp = code(x, y, z) tmp = x + (y / ((1.1283791670955126 * exp(z)) - (x * y))); end
code[x_, y_, z_] := N[(x + N[(y / N[(N[(1.1283791670955126 * N[Exp[z], $MachinePrecision]), $MachinePrecision] - N[(x * y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \frac{y}{1.1283791670955126 \cdot e^{z} - x \cdot y}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y z) :precision binary64 (+ x (/ y (- (* 1.1283791670955126 (exp z)) (* x y)))))
double code(double x, double y, double z) {
return x + (y / ((1.1283791670955126 * exp(z)) - (x * y)));
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = x + (y / ((1.1283791670955126d0 * exp(z)) - (x * y)))
end function
public static double code(double x, double y, double z) {
return x + (y / ((1.1283791670955126 * Math.exp(z)) - (x * y)));
}
def code(x, y, z): return x + (y / ((1.1283791670955126 * math.exp(z)) - (x * y)))
function code(x, y, z) return Float64(x + Float64(y / Float64(Float64(1.1283791670955126 * exp(z)) - Float64(x * y)))) end
function tmp = code(x, y, z) tmp = x + (y / ((1.1283791670955126 * exp(z)) - (x * y))); end
code[x_, y_, z_] := N[(x + N[(y / N[(N[(1.1283791670955126 * N[Exp[z], $MachinePrecision]), $MachinePrecision] - N[(x * y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \frac{y}{1.1283791670955126 \cdot e^{z} - x \cdot y}
\end{array}
(FPCore (x y z) :precision binary64 (if (<= (exp z) 2.2e-76) (+ x (/ -1.0 x)) (if (<= (exp z) 1.0) (+ x (/ y (- 1.1283791670955126 (* x y)))) x)))
double code(double x, double y, double z) {
double tmp;
if (exp(z) <= 2.2e-76) {
tmp = x + (-1.0 / x);
} else if (exp(z) <= 1.0) {
tmp = x + (y / (1.1283791670955126 - (x * y)));
} else {
tmp = x;
}
return tmp;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8) :: tmp
if (exp(z) <= 2.2d-76) then
tmp = x + ((-1.0d0) / x)
else if (exp(z) <= 1.0d0) then
tmp = x + (y / (1.1283791670955126d0 - (x * y)))
else
tmp = x
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (Math.exp(z) <= 2.2e-76) {
tmp = x + (-1.0 / x);
} else if (Math.exp(z) <= 1.0) {
tmp = x + (y / (1.1283791670955126 - (x * y)));
} else {
tmp = x;
}
return tmp;
}
def code(x, y, z): tmp = 0 if math.exp(z) <= 2.2e-76: tmp = x + (-1.0 / x) elif math.exp(z) <= 1.0: tmp = x + (y / (1.1283791670955126 - (x * y))) else: tmp = x return tmp
function code(x, y, z) tmp = 0.0 if (exp(z) <= 2.2e-76) tmp = Float64(x + Float64(-1.0 / x)); elseif (exp(z) <= 1.0) tmp = Float64(x + Float64(y / Float64(1.1283791670955126 - Float64(x * y)))); else tmp = x; end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (exp(z) <= 2.2e-76) tmp = x + (-1.0 / x); elseif (exp(z) <= 1.0) tmp = x + (y / (1.1283791670955126 - (x * y))); else tmp = x; end tmp_2 = tmp; end
code[x_, y_, z_] := If[LessEqual[N[Exp[z], $MachinePrecision], 2.2e-76], N[(x + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision], If[LessEqual[N[Exp[z], $MachinePrecision], 1.0], N[(x + N[(y / N[(1.1283791670955126 - N[(x * y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], x]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;e^{z} \leq 2.2 \cdot 10^{-76}:\\
\;\;\;\;x + \frac{-1}{x}\\
\mathbf{elif}\;e^{z} \leq 1:\\
\;\;\;\;x + \frac{y}{1.1283791670955126 - x \cdot y}\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if (exp.f64 z) < 2.19999999999999999e-76Initial program 85.4%
Taylor expanded in y around inf 100.0%
if 2.19999999999999999e-76 < (exp.f64 z) < 1Initial program 99.9%
remove-double-neg99.9%
distribute-frac-neg99.9%
unsub-neg99.9%
distribute-frac-neg99.9%
distribute-neg-frac299.9%
neg-sub099.9%
associate--r-99.9%
neg-sub099.9%
+-commutative99.9%
fma-define99.9%
*-commutative99.9%
distribute-rgt-neg-in99.9%
metadata-eval99.9%
Simplified99.9%
Taylor expanded in z around 0 99.9%
if 1 < (exp.f64 z) Initial program 92.4%
Taylor expanded in x around inf 100.0%
Final simplification99.9%
(FPCore (x y z) :precision binary64 (if (<= (exp z) 0.0) (+ x (/ -1.0 x)) (- x (/ y (fma x y (* (exp z) -1.1283791670955126))))))
double code(double x, double y, double z) {
double tmp;
if (exp(z) <= 0.0) {
tmp = x + (-1.0 / x);
} else {
tmp = x - (y / fma(x, y, (exp(z) * -1.1283791670955126)));
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (exp(z) <= 0.0) tmp = Float64(x + Float64(-1.0 / x)); else tmp = Float64(x - Float64(y / fma(x, y, Float64(exp(z) * -1.1283791670955126)))); end return tmp end
code[x_, y_, z_] := If[LessEqual[N[Exp[z], $MachinePrecision], 0.0], N[(x + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision], N[(x - N[(y / N[(x * y + N[(N[Exp[z], $MachinePrecision] * -1.1283791670955126), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;e^{z} \leq 0:\\
\;\;\;\;x + \frac{-1}{x}\\
\mathbf{else}:\\
\;\;\;\;x - \frac{y}{\mathsf{fma}\left(x, y, e^{z} \cdot -1.1283791670955126\right)}\\
\end{array}
\end{array}
if (exp.f64 z) < 0.0Initial program 85.4%
Taylor expanded in y around inf 100.0%
if 0.0 < (exp.f64 z) Initial program 97.3%
remove-double-neg97.3%
distribute-frac-neg97.3%
unsub-neg97.3%
distribute-frac-neg97.3%
distribute-neg-frac297.3%
neg-sub097.3%
associate--r-97.3%
neg-sub097.3%
+-commutative97.3%
fma-define99.9%
*-commutative99.9%
distribute-rgt-neg-in99.9%
metadata-eval99.9%
Simplified99.9%
Final simplification99.9%
(FPCore (x y z) :precision binary64 (let* ((t_0 (+ x (/ y (- (* (exp z) 1.1283791670955126) (* x y)))))) (if (<= t_0 2e+208) t_0 (+ x (/ -1.0 x)))))
double code(double x, double y, double z) {
double t_0 = x + (y / ((exp(z) * 1.1283791670955126) - (x * y)));
double tmp;
if (t_0 <= 2e+208) {
tmp = t_0;
} else {
tmp = x + (-1.0 / x);
}
return tmp;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8) :: t_0
real(8) :: tmp
t_0 = x + (y / ((exp(z) * 1.1283791670955126d0) - (x * y)))
if (t_0 <= 2d+208) then
tmp = t_0
else
tmp = x + ((-1.0d0) / x)
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double t_0 = x + (y / ((Math.exp(z) * 1.1283791670955126) - (x * y)));
double tmp;
if (t_0 <= 2e+208) {
tmp = t_0;
} else {
tmp = x + (-1.0 / x);
}
return tmp;
}
def code(x, y, z): t_0 = x + (y / ((math.exp(z) * 1.1283791670955126) - (x * y))) tmp = 0 if t_0 <= 2e+208: tmp = t_0 else: tmp = x + (-1.0 / x) return tmp
function code(x, y, z) t_0 = Float64(x + Float64(y / Float64(Float64(exp(z) * 1.1283791670955126) - Float64(x * y)))) tmp = 0.0 if (t_0 <= 2e+208) tmp = t_0; else tmp = Float64(x + Float64(-1.0 / x)); end return tmp end
function tmp_2 = code(x, y, z) t_0 = x + (y / ((exp(z) * 1.1283791670955126) - (x * y))); tmp = 0.0; if (t_0 <= 2e+208) tmp = t_0; else tmp = x + (-1.0 / x); end tmp_2 = tmp; end
code[x_, y_, z_] := Block[{t$95$0 = N[(x + N[(y / N[(N[(N[Exp[z], $MachinePrecision] * 1.1283791670955126), $MachinePrecision] - N[(x * y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 2e+208], t$95$0, N[(x + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := x + \frac{y}{e^{z} \cdot 1.1283791670955126 - x \cdot y}\\
\mathbf{if}\;t\_0 \leq 2 \cdot 10^{+208}:\\
\;\;\;\;t\_0\\
\mathbf{else}:\\
\;\;\;\;x + \frac{-1}{x}\\
\end{array}
\end{array}
if (+.f64 x (/.f64 y (-.f64 (*.f64 #s(literal 5641895835477563/5000000000000000 binary64) (exp.f64 z)) (*.f64 x y)))) < 2e208Initial program 98.9%
if 2e208 < (+.f64 x (/.f64 y (-.f64 (*.f64 #s(literal 5641895835477563/5000000000000000 binary64) (exp.f64 z)) (*.f64 x y)))) Initial program 68.4%
Taylor expanded in y around inf 100.0%
Final simplification99.0%
(FPCore (x y z) :precision binary64 (if (<= y -2.65e+36) x (if (<= y 1.75e+34) (- x (* y -0.8862269254527579)) x)))
double code(double x, double y, double z) {
double tmp;
if (y <= -2.65e+36) {
tmp = x;
} else if (y <= 1.75e+34) {
tmp = x - (y * -0.8862269254527579);
} else {
tmp = x;
}
return tmp;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8) :: tmp
if (y <= (-2.65d+36)) then
tmp = x
else if (y <= 1.75d+34) then
tmp = x - (y * (-0.8862269254527579d0))
else
tmp = x
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (y <= -2.65e+36) {
tmp = x;
} else if (y <= 1.75e+34) {
tmp = x - (y * -0.8862269254527579);
} else {
tmp = x;
}
return tmp;
}
def code(x, y, z): tmp = 0 if y <= -2.65e+36: tmp = x elif y <= 1.75e+34: tmp = x - (y * -0.8862269254527579) else: tmp = x return tmp
function code(x, y, z) tmp = 0.0 if (y <= -2.65e+36) tmp = x; elseif (y <= 1.75e+34) tmp = Float64(x - Float64(y * -0.8862269254527579)); else tmp = x; end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (y <= -2.65e+36) tmp = x; elseif (y <= 1.75e+34) tmp = x - (y * -0.8862269254527579); else tmp = x; end tmp_2 = tmp; end
code[x_, y_, z_] := If[LessEqual[y, -2.65e+36], x, If[LessEqual[y, 1.75e+34], N[(x - N[(y * -0.8862269254527579), $MachinePrecision]), $MachinePrecision], x]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -2.65 \cdot 10^{+36}:\\
\;\;\;\;x\\
\mathbf{elif}\;y \leq 1.75 \cdot 10^{+34}:\\
\;\;\;\;x - y \cdot -0.8862269254527579\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if y < -2.65e36 or 1.74999999999999999e34 < y Initial program 95.6%
Taylor expanded in x around inf 65.8%
if -2.65e36 < y < 1.74999999999999999e34Initial program 93.4%
remove-double-neg93.4%
distribute-frac-neg93.4%
unsub-neg93.4%
distribute-frac-neg93.4%
distribute-neg-frac293.4%
neg-sub093.5%
associate--r-93.5%
neg-sub093.7%
+-commutative93.7%
fma-define93.7%
*-commutative93.7%
distribute-rgt-neg-in93.7%
metadata-eval93.7%
Simplified93.7%
Taylor expanded in y around 0 75.4%
*-commutative75.4%
Simplified75.4%
Taylor expanded in z around 0 79.8%
Final simplification73.4%
(FPCore (x y z) :precision binary64 (if (<= z -2.3e-227) (+ x (/ -1.0 x)) (if (<= z 2.55e-110) (- x (* y -0.8862269254527579)) x)))
double code(double x, double y, double z) {
double tmp;
if (z <= -2.3e-227) {
tmp = x + (-1.0 / x);
} else if (z <= 2.55e-110) {
tmp = x - (y * -0.8862269254527579);
} else {
tmp = x;
}
return tmp;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8) :: tmp
if (z <= (-2.3d-227)) then
tmp = x + ((-1.0d0) / x)
else if (z <= 2.55d-110) then
tmp = x - (y * (-0.8862269254527579d0))
else
tmp = x
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (z <= -2.3e-227) {
tmp = x + (-1.0 / x);
} else if (z <= 2.55e-110) {
tmp = x - (y * -0.8862269254527579);
} else {
tmp = x;
}
return tmp;
}
def code(x, y, z): tmp = 0 if z <= -2.3e-227: tmp = x + (-1.0 / x) elif z <= 2.55e-110: tmp = x - (y * -0.8862269254527579) else: tmp = x return tmp
function code(x, y, z) tmp = 0.0 if (z <= -2.3e-227) tmp = Float64(x + Float64(-1.0 / x)); elseif (z <= 2.55e-110) tmp = Float64(x - Float64(y * -0.8862269254527579)); else tmp = x; end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (z <= -2.3e-227) tmp = x + (-1.0 / x); elseif (z <= 2.55e-110) tmp = x - (y * -0.8862269254527579); else tmp = x; end tmp_2 = tmp; end
code[x_, y_, z_] := If[LessEqual[z, -2.3e-227], N[(x + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision], If[LessEqual[z, 2.55e-110], N[(x - N[(y * -0.8862269254527579), $MachinePrecision]), $MachinePrecision], x]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;z \leq -2.3 \cdot 10^{-227}:\\
\;\;\;\;x + \frac{-1}{x}\\
\mathbf{elif}\;z \leq 2.55 \cdot 10^{-110}:\\
\;\;\;\;x - y \cdot -0.8862269254527579\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if z < -2.30000000000000012e-227Initial program 91.7%
Taylor expanded in y around inf 90.1%
if -2.30000000000000012e-227 < z < 2.5500000000000001e-110Initial program 99.8%
remove-double-neg99.8%
distribute-frac-neg99.8%
unsub-neg99.8%
distribute-frac-neg99.8%
distribute-neg-frac299.8%
neg-sub099.8%
associate--r-99.8%
neg-sub099.8%
+-commutative99.8%
fma-define99.8%
*-commutative99.8%
distribute-rgt-neg-in99.8%
metadata-eval99.8%
Simplified99.8%
Taylor expanded in y around 0 67.3%
*-commutative67.3%
Simplified67.3%
Taylor expanded in z around 0 67.3%
if 2.5500000000000001e-110 < z Initial program 93.9%
Taylor expanded in x around inf 96.5%
Final simplification86.4%
(FPCore (x y z) :precision binary64 x)
double code(double x, double y, double z) {
return x;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = x
end function
public static double code(double x, double y, double z) {
return x;
}
def code(x, y, z): return x
function code(x, y, z) return x end
function tmp = code(x, y, z) tmp = x; end
code[x_, y_, z_] := x
\begin{array}{l}
\\
x
\end{array}
Initial program 94.4%
Taylor expanded in x around inf 68.3%
Final simplification68.3%
(FPCore (x y z) :precision binary64 (+ x (/ 1.0 (- (* (/ 1.1283791670955126 y) (exp z)) x))))
double code(double x, double y, double z) {
return x + (1.0 / (((1.1283791670955126 / y) * exp(z)) - x));
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = x + (1.0d0 / (((1.1283791670955126d0 / y) * exp(z)) - x))
end function
public static double code(double x, double y, double z) {
return x + (1.0 / (((1.1283791670955126 / y) * Math.exp(z)) - x));
}
def code(x, y, z): return x + (1.0 / (((1.1283791670955126 / y) * math.exp(z)) - x))
function code(x, y, z) return Float64(x + Float64(1.0 / Float64(Float64(Float64(1.1283791670955126 / y) * exp(z)) - x))) end
function tmp = code(x, y, z) tmp = x + (1.0 / (((1.1283791670955126 / y) * exp(z)) - x)); end
code[x_, y_, z_] := N[(x + N[(1.0 / N[(N[(N[(1.1283791670955126 / y), $MachinePrecision] * N[Exp[z], $MachinePrecision]), $MachinePrecision] - x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \frac{1}{\frac{1.1283791670955126}{y} \cdot e^{z} - x}
\end{array}
herbie shell --seed 2024059
(FPCore (x y z)
:name "Numeric.SpecFunctions:invErfc from math-functions-0.1.5.2, A"
:precision binary64
:alt
(+ x (/ 1.0 (- (* (/ 1.1283791670955126 y) (exp z)) x)))
(+ x (/ y (- (* 1.1283791670955126 (exp z)) (* x y)))))