
(FPCore (x y) :precision binary64 (- x (/ y (+ 1.0 (/ (* x y) 2.0)))))
double code(double x, double y) {
return x - (y / (1.0 + ((x * y) / 2.0)));
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x - (y / (1.0d0 + ((x * y) / 2.0d0)))
end function
public static double code(double x, double y) {
return x - (y / (1.0 + ((x * y) / 2.0)));
}
def code(x, y): return x - (y / (1.0 + ((x * y) / 2.0)))
function code(x, y) return Float64(x - Float64(y / Float64(1.0 + Float64(Float64(x * y) / 2.0)))) end
function tmp = code(x, y) tmp = x - (y / (1.0 + ((x * y) / 2.0))); end
code[x_, y_] := N[(x - N[(y / N[(1.0 + N[(N[(x * y), $MachinePrecision] / 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x - \frac{y}{1 + \frac{x \cdot y}{2}}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (- x (/ y (+ 1.0 (/ (* x y) 2.0)))))
double code(double x, double y) {
return x - (y / (1.0 + ((x * y) / 2.0)));
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x - (y / (1.0d0 + ((x * y) / 2.0d0)))
end function
public static double code(double x, double y) {
return x - (y / (1.0 + ((x * y) / 2.0)));
}
def code(x, y): return x - (y / (1.0 + ((x * y) / 2.0)))
function code(x, y) return Float64(x - Float64(y / Float64(1.0 + Float64(Float64(x * y) / 2.0)))) end
function tmp = code(x, y) tmp = x - (y / (1.0 + ((x * y) / 2.0))); end
code[x_, y_] := N[(x - N[(y / N[(1.0 + N[(N[(x * y), $MachinePrecision] / 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x - \frac{y}{1 + \frac{x \cdot y}{2}}
\end{array}
(FPCore (x y) :precision binary64 (- x (/ y (fma (* y 0.5) x 1.0))))
double code(double x, double y) {
return x - (y / fma((y * 0.5), x, 1.0));
}
function code(x, y) return Float64(x - Float64(y / fma(Float64(y * 0.5), x, 1.0))) end
code[x_, y_] := N[(x - N[(y / N[(N[(y * 0.5), $MachinePrecision] * x + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x - \frac{y}{\mathsf{fma}\left(y \cdot 0.5, x, 1\right)}
\end{array}
Initial program 99.9%
lift-*.f64N/A
lift-/.f64N/A
+-commutativeN/A
lift-/.f64N/A
lift-*.f64N/A
associate-/l*N/A
*-commutativeN/A
lower-fma.f64N/A
div-invN/A
lower-*.f64N/A
metadata-eval99.9
Applied egg-rr99.9%
(FPCore (x y) :precision binary64 (let* ((t_0 (- x (/ 2.0 x)))) (if (<= y -1e+79) t_0 (if (<= y 1.44e+159) (- x y) t_0))))
double code(double x, double y) {
double t_0 = x - (2.0 / x);
double tmp;
if (y <= -1e+79) {
tmp = t_0;
} else if (y <= 1.44e+159) {
tmp = x - y;
} else {
tmp = t_0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: t_0
real(8) :: tmp
t_0 = x - (2.0d0 / x)
if (y <= (-1d+79)) then
tmp = t_0
else if (y <= 1.44d+159) then
tmp = x - y
else
tmp = t_0
end if
code = tmp
end function
public static double code(double x, double y) {
double t_0 = x - (2.0 / x);
double tmp;
if (y <= -1e+79) {
tmp = t_0;
} else if (y <= 1.44e+159) {
tmp = x - y;
} else {
tmp = t_0;
}
return tmp;
}
def code(x, y): t_0 = x - (2.0 / x) tmp = 0 if y <= -1e+79: tmp = t_0 elif y <= 1.44e+159: tmp = x - y else: tmp = t_0 return tmp
function code(x, y) t_0 = Float64(x - Float64(2.0 / x)) tmp = 0.0 if (y <= -1e+79) tmp = t_0; elseif (y <= 1.44e+159) tmp = Float64(x - y); else tmp = t_0; end return tmp end
function tmp_2 = code(x, y) t_0 = x - (2.0 / x); tmp = 0.0; if (y <= -1e+79) tmp = t_0; elseif (y <= 1.44e+159) tmp = x - y; else tmp = t_0; end tmp_2 = tmp; end
code[x_, y_] := Block[{t$95$0 = N[(x - N[(2.0 / x), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -1e+79], t$95$0, If[LessEqual[y, 1.44e+159], N[(x - y), $MachinePrecision], t$95$0]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := x - \frac{2}{x}\\
\mathbf{if}\;y \leq -1 \cdot 10^{+79}:\\
\;\;\;\;t\_0\\
\mathbf{elif}\;y \leq 1.44 \cdot 10^{+159}:\\
\;\;\;\;x - y\\
\mathbf{else}:\\
\;\;\;\;t\_0\\
\end{array}
\end{array}
if y < -9.99999999999999967e78 or 1.43999999999999995e159 < y Initial program 99.8%
Taylor expanded in x around inf
lower-/.f6485.3
Simplified85.3%
if -9.99999999999999967e78 < y < 1.43999999999999995e159Initial program 100.0%
Taylor expanded in y around 0
*-commutativeN/A
+-commutativeN/A
distribute-lft1-inN/A
associate-*r*N/A
associate-*r*N/A
unpow2N/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-*.f64N/A
unpow2N/A
lower-*.f6484.6
Simplified84.6%
Taylor expanded in y around 0
mul-1-negN/A
unsub-negN/A
lower--.f6495.3
Simplified95.3%
(FPCore (x y) :precision binary64 (if (<= x -2.5) (+ x -1.0) (if (<= x 5.4e-6) (- x y) (+ x -1.0))))
double code(double x, double y) {
double tmp;
if (x <= -2.5) {
tmp = x + -1.0;
} else if (x <= 5.4e-6) {
tmp = x - y;
} else {
tmp = x + -1.0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (x <= (-2.5d0)) then
tmp = x + (-1.0d0)
else if (x <= 5.4d-6) then
tmp = x - y
else
tmp = x + (-1.0d0)
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -2.5) {
tmp = x + -1.0;
} else if (x <= 5.4e-6) {
tmp = x - y;
} else {
tmp = x + -1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -2.5: tmp = x + -1.0 elif x <= 5.4e-6: tmp = x - y else: tmp = x + -1.0 return tmp
function code(x, y) tmp = 0.0 if (x <= -2.5) tmp = Float64(x + -1.0); elseif (x <= 5.4e-6) tmp = Float64(x - y); else tmp = Float64(x + -1.0); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -2.5) tmp = x + -1.0; elseif (x <= 5.4e-6) tmp = x - y; else tmp = x + -1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -2.5], N[(x + -1.0), $MachinePrecision], If[LessEqual[x, 5.4e-6], N[(x - y), $MachinePrecision], N[(x + -1.0), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -2.5:\\
\;\;\;\;x + -1\\
\mathbf{elif}\;x \leq 5.4 \cdot 10^{-6}:\\
\;\;\;\;x - y\\
\mathbf{else}:\\
\;\;\;\;x + -1\\
\end{array}
\end{array}
if x < -2.5 or 5.39999999999999997e-6 < x Initial program 100.0%
Taylor expanded in y around 0
sub-negN/A
metadata-evalN/A
lower-+.f6495.2
Simplified95.2%
if -2.5 < x < 5.39999999999999997e-6Initial program 99.9%
Taylor expanded in y around 0
*-commutativeN/A
+-commutativeN/A
distribute-lft1-inN/A
associate-*r*N/A
associate-*r*N/A
unpow2N/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-*.f64N/A
unpow2N/A
lower-*.f6474.6
Simplified74.6%
Taylor expanded in y around 0
mul-1-negN/A
unsub-negN/A
lower--.f6480.0
Simplified80.0%
(FPCore (x y) :precision binary64 (if (<= x -4.4e-68) (+ x -1.0) (if (<= x 4.7e-26) (- y) (+ x -1.0))))
double code(double x, double y) {
double tmp;
if (x <= -4.4e-68) {
tmp = x + -1.0;
} else if (x <= 4.7e-26) {
tmp = -y;
} else {
tmp = x + -1.0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (x <= (-4.4d-68)) then
tmp = x + (-1.0d0)
else if (x <= 4.7d-26) then
tmp = -y
else
tmp = x + (-1.0d0)
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -4.4e-68) {
tmp = x + -1.0;
} else if (x <= 4.7e-26) {
tmp = -y;
} else {
tmp = x + -1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -4.4e-68: tmp = x + -1.0 elif x <= 4.7e-26: tmp = -y else: tmp = x + -1.0 return tmp
function code(x, y) tmp = 0.0 if (x <= -4.4e-68) tmp = Float64(x + -1.0); elseif (x <= 4.7e-26) tmp = Float64(-y); else tmp = Float64(x + -1.0); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -4.4e-68) tmp = x + -1.0; elseif (x <= 4.7e-26) tmp = -y; else tmp = x + -1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -4.4e-68], N[(x + -1.0), $MachinePrecision], If[LessEqual[x, 4.7e-26], (-y), N[(x + -1.0), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -4.4 \cdot 10^{-68}:\\
\;\;\;\;x + -1\\
\mathbf{elif}\;x \leq 4.7 \cdot 10^{-26}:\\
\;\;\;\;-y\\
\mathbf{else}:\\
\;\;\;\;x + -1\\
\end{array}
\end{array}
if x < -4.40000000000000005e-68 or 4.69999999999999989e-26 < x Initial program 100.0%
Taylor expanded in y around 0
sub-negN/A
metadata-evalN/A
lower-+.f6485.6
Simplified85.6%
if -4.40000000000000005e-68 < x < 4.69999999999999989e-26Initial program 99.9%
Taylor expanded in y around 0
*-commutativeN/A
+-commutativeN/A
distribute-lft1-inN/A
associate-*r*N/A
associate-*r*N/A
unpow2N/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-*.f64N/A
unpow2N/A
lower-*.f6475.6
Simplified75.6%
Taylor expanded in x around 0
mul-1-negN/A
lower-neg.f6462.9
Simplified62.9%
(FPCore (x y) :precision binary64 (- y))
double code(double x, double y) {
return -y;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = -y
end function
public static double code(double x, double y) {
return -y;
}
def code(x, y): return -y
function code(x, y) return Float64(-y) end
function tmp = code(x, y) tmp = -y; end
code[x_, y_] := (-y)
\begin{array}{l}
\\
-y
\end{array}
Initial program 99.9%
Taylor expanded in y around 0
*-commutativeN/A
+-commutativeN/A
distribute-lft1-inN/A
associate-*r*N/A
associate-*r*N/A
unpow2N/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-*.f64N/A
unpow2N/A
lower-*.f6462.4
Simplified62.4%
Taylor expanded in x around 0
mul-1-negN/A
lower-neg.f6430.7
Simplified30.7%
(FPCore (x y) :precision binary64 -2.0)
double code(double x, double y) {
return -2.0;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = -2.0d0
end function
public static double code(double x, double y) {
return -2.0;
}
def code(x, y): return -2.0
function code(x, y) return -2.0 end
function tmp = code(x, y) tmp = -2.0; end
code[x_, y_] := -2.0
\begin{array}{l}
\\
-2
\end{array}
Initial program 99.9%
Taylor expanded in y around inf
Simplified47.8%
Taylor expanded in x around 0
Simplified4.0%
herbie shell --seed 2024214
(FPCore (x y)
:name "Data.Number.Erf:$cinvnormcdf from erf-2.0.0.0, B"
:precision binary64
(- x (/ y (+ 1.0 (/ (* x y) 2.0)))))