
(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 (+ 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}
Initial program 99.9%
(FPCore (x y)
:precision binary64
(if (<= x -2.1e-8)
x
(if (<= x -9.5e-71)
(/ -2.0 x)
(if (<= x 8.2e-70) (- x y) (if (<= x 2e-12) (/ -2.0 x) x)))))
double code(double x, double y) {
double tmp;
if (x <= -2.1e-8) {
tmp = x;
} else if (x <= -9.5e-71) {
tmp = -2.0 / x;
} else if (x <= 8.2e-70) {
tmp = x - y;
} else if (x <= 2e-12) {
tmp = -2.0 / x;
} else {
tmp = x;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (x <= (-2.1d-8)) then
tmp = x
else if (x <= (-9.5d-71)) then
tmp = (-2.0d0) / x
else if (x <= 8.2d-70) then
tmp = x - y
else if (x <= 2d-12) then
tmp = (-2.0d0) / x
else
tmp = x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -2.1e-8) {
tmp = x;
} else if (x <= -9.5e-71) {
tmp = -2.0 / x;
} else if (x <= 8.2e-70) {
tmp = x - y;
} else if (x <= 2e-12) {
tmp = -2.0 / x;
} else {
tmp = x;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -2.1e-8: tmp = x elif x <= -9.5e-71: tmp = -2.0 / x elif x <= 8.2e-70: tmp = x - y elif x <= 2e-12: tmp = -2.0 / x else: tmp = x return tmp
function code(x, y) tmp = 0.0 if (x <= -2.1e-8) tmp = x; elseif (x <= -9.5e-71) tmp = Float64(-2.0 / x); elseif (x <= 8.2e-70) tmp = Float64(x - y); elseif (x <= 2e-12) tmp = Float64(-2.0 / x); else tmp = x; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -2.1e-8) tmp = x; elseif (x <= -9.5e-71) tmp = -2.0 / x; elseif (x <= 8.2e-70) tmp = x - y; elseif (x <= 2e-12) tmp = -2.0 / x; else tmp = x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -2.1e-8], x, If[LessEqual[x, -9.5e-71], N[(-2.0 / x), $MachinePrecision], If[LessEqual[x, 8.2e-70], N[(x - y), $MachinePrecision], If[LessEqual[x, 2e-12], N[(-2.0 / x), $MachinePrecision], x]]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -2.1 \cdot 10^{-8}:\\
\;\;\;\;x\\
\mathbf{elif}\;x \leq -9.5 \cdot 10^{-71}:\\
\;\;\;\;\frac{-2}{x}\\
\mathbf{elif}\;x \leq 8.2 \cdot 10^{-70}:\\
\;\;\;\;x - y\\
\mathbf{elif}\;x \leq 2 \cdot 10^{-12}:\\
\;\;\;\;\frac{-2}{x}\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if x < -2.09999999999999994e-8 or 1.99999999999999996e-12 < x Initial program 100.0%
Taylor expanded in x around inf 98.2%
if -2.09999999999999994e-8 < x < -9.4999999999999994e-71 or 8.19999999999999955e-70 < x < 1.99999999999999996e-12Initial program 99.7%
Taylor expanded in y around inf 68.2%
associate-*r/68.2%
metadata-eval68.2%
Simplified68.2%
Taylor expanded in x around 0 68.2%
if -9.4999999999999994e-71 < x < 8.19999999999999955e-70Initial program 99.9%
Taylor expanded in y around 0 85.9%
neg-mul-185.9%
unsub-neg85.9%
Simplified85.9%
(FPCore (x y) :precision binary64 (if (or (<= y -1.02e+40) (not (<= y 3.5e+63))) (- x (/ 2.0 x)) (- x y)))
double code(double x, double y) {
double tmp;
if ((y <= -1.02e+40) || !(y <= 3.5e+63)) {
tmp = x - (2.0 / x);
} else {
tmp = x - y;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if ((y <= (-1.02d+40)) .or. (.not. (y <= 3.5d+63))) then
tmp = x - (2.0d0 / x)
else
tmp = x - y
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((y <= -1.02e+40) || !(y <= 3.5e+63)) {
tmp = x - (2.0 / x);
} else {
tmp = x - y;
}
return tmp;
}
def code(x, y): tmp = 0 if (y <= -1.02e+40) or not (y <= 3.5e+63): tmp = x - (2.0 / x) else: tmp = x - y return tmp
function code(x, y) tmp = 0.0 if ((y <= -1.02e+40) || !(y <= 3.5e+63)) tmp = Float64(x - Float64(2.0 / x)); else tmp = Float64(x - y); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((y <= -1.02e+40) || ~((y <= 3.5e+63))) tmp = x - (2.0 / x); else tmp = x - y; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[y, -1.02e+40], N[Not[LessEqual[y, 3.5e+63]], $MachinePrecision]], N[(x - N[(2.0 / x), $MachinePrecision]), $MachinePrecision], N[(x - y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.02 \cdot 10^{+40} \lor \neg \left(y \leq 3.5 \cdot 10^{+63}\right):\\
\;\;\;\;x - \frac{2}{x}\\
\mathbf{else}:\\
\;\;\;\;x - y\\
\end{array}
\end{array}
if y < -1.02e40 or 3.50000000000000029e63 < y Initial program 99.9%
Taylor expanded in y around inf 82.5%
associate-*r/82.5%
metadata-eval82.5%
Simplified82.5%
if -1.02e40 < y < 3.50000000000000029e63Initial program 100.0%
Taylor expanded in y around 0 99.3%
neg-mul-199.3%
unsub-neg99.3%
Simplified99.3%
Final simplification92.4%
(FPCore (x y) :precision binary64 (if (<= x -0.006) x (if (<= x 1.4) (- x y) x)))
double code(double x, double y) {
double tmp;
if (x <= -0.006) {
tmp = x;
} else if (x <= 1.4) {
tmp = x - y;
} else {
tmp = x;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (x <= (-0.006d0)) then
tmp = x
else if (x <= 1.4d0) then
tmp = x - y
else
tmp = x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -0.006) {
tmp = x;
} else if (x <= 1.4) {
tmp = x - y;
} else {
tmp = x;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -0.006: tmp = x elif x <= 1.4: tmp = x - y else: tmp = x return tmp
function code(x, y) tmp = 0.0 if (x <= -0.006) tmp = x; elseif (x <= 1.4) tmp = Float64(x - y); else tmp = x; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -0.006) tmp = x; elseif (x <= 1.4) tmp = x - y; else tmp = x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -0.006], x, If[LessEqual[x, 1.4], N[(x - y), $MachinePrecision], x]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -0.006:\\
\;\;\;\;x\\
\mathbf{elif}\;x \leq 1.4:\\
\;\;\;\;x - y\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if x < -0.0060000000000000001 or 1.3999999999999999 < x Initial program 100.0%
Taylor expanded in x around inf 99.0%
if -0.0060000000000000001 < x < 1.3999999999999999Initial program 99.9%
Taylor expanded in y around 0 72.6%
neg-mul-172.6%
unsub-neg72.6%
Simplified72.6%
(FPCore (x y) :precision binary64 (if (<= x -1.5e-60) x (if (<= x 2.2e-110) (- y) x)))
double code(double x, double y) {
double tmp;
if (x <= -1.5e-60) {
tmp = x;
} else if (x <= 2.2e-110) {
tmp = -y;
} else {
tmp = x;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (x <= (-1.5d-60)) then
tmp = x
else if (x <= 2.2d-110) then
tmp = -y
else
tmp = x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -1.5e-60) {
tmp = x;
} else if (x <= 2.2e-110) {
tmp = -y;
} else {
tmp = x;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -1.5e-60: tmp = x elif x <= 2.2e-110: tmp = -y else: tmp = x return tmp
function code(x, y) tmp = 0.0 if (x <= -1.5e-60) tmp = x; elseif (x <= 2.2e-110) tmp = Float64(-y); else tmp = x; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -1.5e-60) tmp = x; elseif (x <= 2.2e-110) tmp = -y; else tmp = x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -1.5e-60], x, If[LessEqual[x, 2.2e-110], (-y), x]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.5 \cdot 10^{-60}:\\
\;\;\;\;x\\
\mathbf{elif}\;x \leq 2.2 \cdot 10^{-110}:\\
\;\;\;\;-y\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if x < -1.50000000000000009e-60 or 2.1999999999999999e-110 < x Initial program 99.9%
Taylor expanded in x around inf 84.4%
if -1.50000000000000009e-60 < x < 2.1999999999999999e-110Initial program 99.9%
Taylor expanded in x around 0 70.0%
neg-mul-170.0%
Simplified70.0%
(FPCore (x y) :precision binary64 x)
double code(double x, double y) {
return x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x
end function
public static double code(double x, double y) {
return x;
}
def code(x, y): return x
function code(x, y) return x end
function tmp = code(x, y) tmp = x; end
code[x_, y_] := x
\begin{array}{l}
\\
x
\end{array}
Initial program 99.9%
Taylor expanded in x around inf 58.7%
herbie shell --seed 2024170
(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)))))