
(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 100.0%
Final simplification100.0%
(FPCore (x y) :precision binary64 (if (<= x -8e-29) x (if (<= x -4.8e-94) (/ -2.0 x) (if (<= x 1.4) (- x y) x))))
double code(double x, double y) {
double tmp;
if (x <= -8e-29) {
tmp = x;
} else if (x <= -4.8e-94) {
tmp = -2.0 / 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 <= (-8d-29)) then
tmp = x
else if (x <= (-4.8d-94)) then
tmp = (-2.0d0) / 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 <= -8e-29) {
tmp = x;
} else if (x <= -4.8e-94) {
tmp = -2.0 / x;
} else if (x <= 1.4) {
tmp = x - y;
} else {
tmp = x;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -8e-29: tmp = x elif x <= -4.8e-94: tmp = -2.0 / x elif x <= 1.4: tmp = x - y else: tmp = x return tmp
function code(x, y) tmp = 0.0 if (x <= -8e-29) tmp = x; elseif (x <= -4.8e-94) tmp = Float64(-2.0 / 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 <= -8e-29) tmp = x; elseif (x <= -4.8e-94) tmp = -2.0 / x; elseif (x <= 1.4) tmp = x - y; else tmp = x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -8e-29], x, If[LessEqual[x, -4.8e-94], N[(-2.0 / x), $MachinePrecision], If[LessEqual[x, 1.4], N[(x - y), $MachinePrecision], x]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -8 \cdot 10^{-29}:\\
\;\;\;\;x\\
\mathbf{elif}\;x \leq -4.8 \cdot 10^{-94}:\\
\;\;\;\;\frac{-2}{x}\\
\mathbf{elif}\;x \leq 1.4:\\
\;\;\;\;x - y\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if x < -7.99999999999999955e-29 or 1.3999999999999999 < x Initial program 100.0%
Taylor expanded in x around inf 99.2%
if -7.99999999999999955e-29 < x < -4.8e-94Initial program 99.7%
Taylor expanded in y around inf 83.6%
associate-*r/83.6%
metadata-eval83.6%
Simplified83.6%
Taylor expanded in x around 0 83.6%
if -4.8e-94 < x < 1.3999999999999999Initial program 99.9%
Taylor expanded in y around 0 79.5%
neg-mul-179.5%
unsub-neg79.5%
Simplified79.5%
(FPCore (x y) :precision binary64 (if (or (<= y -6e+19) (not (<= y 2e+117))) (- x (/ 2.0 x)) (- x y)))
double code(double x, double y) {
double tmp;
if ((y <= -6e+19) || !(y <= 2e+117)) {
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 <= (-6d+19)) .or. (.not. (y <= 2d+117))) 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 <= -6e+19) || !(y <= 2e+117)) {
tmp = x - (2.0 / x);
} else {
tmp = x - y;
}
return tmp;
}
def code(x, y): tmp = 0 if (y <= -6e+19) or not (y <= 2e+117): tmp = x - (2.0 / x) else: tmp = x - y return tmp
function code(x, y) tmp = 0.0 if ((y <= -6e+19) || !(y <= 2e+117)) 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 <= -6e+19) || ~((y <= 2e+117))) tmp = x - (2.0 / x); else tmp = x - y; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[y, -6e+19], N[Not[LessEqual[y, 2e+117]], $MachinePrecision]], N[(x - N[(2.0 / x), $MachinePrecision]), $MachinePrecision], N[(x - y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -6 \cdot 10^{+19} \lor \neg \left(y \leq 2 \cdot 10^{+117}\right):\\
\;\;\;\;x - \frac{2}{x}\\
\mathbf{else}:\\
\;\;\;\;x - y\\
\end{array}
\end{array}
if y < -6e19 or 2.0000000000000001e117 < y Initial program 99.9%
Taylor expanded in y around inf 86.3%
associate-*r/86.3%
metadata-eval86.3%
Simplified86.3%
if -6e19 < y < 2.0000000000000001e117Initial program 100.0%
Taylor expanded in y around 0 99.1%
neg-mul-199.1%
unsub-neg99.1%
Simplified99.1%
Final simplification94.3%
(FPCore (x y) :precision binary64 (if (<= x -1.4) x (if (<= x 1.4) (- x y) x)))
double code(double x, double y) {
double tmp;
if (x <= -1.4) {
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 <= (-1.4d0)) 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 <= -1.4) {
tmp = x;
} else if (x <= 1.4) {
tmp = x - y;
} else {
tmp = x;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -1.4: tmp = x elif x <= 1.4: tmp = x - y else: tmp = x return tmp
function code(x, y) tmp = 0.0 if (x <= -1.4) 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 <= -1.4) tmp = x; elseif (x <= 1.4) tmp = x - y; else tmp = x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -1.4], x, If[LessEqual[x, 1.4], N[(x - y), $MachinePrecision], x]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.4:\\
\;\;\;\;x\\
\mathbf{elif}\;x \leq 1.4:\\
\;\;\;\;x - y\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if x < -1.3999999999999999 or 1.3999999999999999 < x Initial program 100.0%
Taylor expanded in x around inf 99.2%
if -1.3999999999999999 < x < 1.3999999999999999Initial program 99.9%
Taylor expanded in y around 0 74.1%
neg-mul-174.1%
unsub-neg74.1%
Simplified74.1%
(FPCore (x y) :precision binary64 (if (<= x -1.25e-112) x (if (<= x 7e-168) (- y) x)))
double code(double x, double y) {
double tmp;
if (x <= -1.25e-112) {
tmp = x;
} else if (x <= 7e-168) {
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 <= (-1.25d-112)) then
tmp = x
else if (x <= 7d-168) then
tmp = -y
else
tmp = x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -1.25e-112) {
tmp = x;
} else if (x <= 7e-168) {
tmp = -y;
} else {
tmp = x;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -1.25e-112: tmp = x elif x <= 7e-168: tmp = -y else: tmp = x return tmp
function code(x, y) tmp = 0.0 if (x <= -1.25e-112) tmp = x; elseif (x <= 7e-168) tmp = Float64(-y); else tmp = x; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -1.25e-112) tmp = x; elseif (x <= 7e-168) tmp = -y; else tmp = x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -1.25e-112], x, If[LessEqual[x, 7e-168], (-y), x]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.25 \cdot 10^{-112}:\\
\;\;\;\;x\\
\mathbf{elif}\;x \leq 7 \cdot 10^{-168}:\\
\;\;\;\;-y\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if x < -1.25000000000000011e-112 or 6.99999999999999964e-168 < x Initial program 100.0%
Taylor expanded in x around inf 82.8%
if -1.25000000000000011e-112 < x < 6.99999999999999964e-168Initial program 100.0%
Taylor expanded in x around 0 67.0%
neg-mul-167.0%
Simplified67.0%
(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 100.0%
Taylor expanded in x around inf 66.2%
herbie shell --seed 2024133
(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)))))