
(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%
Final simplification99.9%
(FPCore (x y) :precision binary64 (if (<= x -1.7) x (if (<= x 5.7e-70) (- x y) (if (<= x 2e-10) (/ -2.0 x) x))))
double code(double x, double y) {
double tmp;
if (x <= -1.7) {
tmp = x;
} else if (x <= 5.7e-70) {
tmp = x - y;
} else if (x <= 2e-10) {
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 <= (-1.7d0)) then
tmp = x
else if (x <= 5.7d-70) then
tmp = x - y
else if (x <= 2d-10) 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 <= -1.7) {
tmp = x;
} else if (x <= 5.7e-70) {
tmp = x - y;
} else if (x <= 2e-10) {
tmp = -2.0 / x;
} else {
tmp = x;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -1.7: tmp = x elif x <= 5.7e-70: tmp = x - y elif x <= 2e-10: tmp = -2.0 / x else: tmp = x return tmp
function code(x, y) tmp = 0.0 if (x <= -1.7) tmp = x; elseif (x <= 5.7e-70) tmp = Float64(x - y); elseif (x <= 2e-10) tmp = Float64(-2.0 / x); else tmp = x; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -1.7) tmp = x; elseif (x <= 5.7e-70) tmp = x - y; elseif (x <= 2e-10) tmp = -2.0 / x; else tmp = x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -1.7], x, If[LessEqual[x, 5.7e-70], N[(x - y), $MachinePrecision], If[LessEqual[x, 2e-10], N[(-2.0 / x), $MachinePrecision], x]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.7:\\
\;\;\;\;x\\
\mathbf{elif}\;x \leq 5.7 \cdot 10^{-70}:\\
\;\;\;\;x - y\\
\mathbf{elif}\;x \leq 2 \cdot 10^{-10}:\\
\;\;\;\;\frac{-2}{x}\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if x < -1.69999999999999996 or 2.00000000000000007e-10 < x Initial program 100.0%
Taylor expanded in x around inf 99.5%
if -1.69999999999999996 < x < 5.70000000000000028e-70Initial program 99.9%
Taylor expanded in y around 0 73.0%
neg-mul-173.0%
unsub-neg73.0%
Simplified73.0%
if 5.70000000000000028e-70 < x < 2.00000000000000007e-10Initial program 99.9%
Taylor expanded in y around inf 62.7%
associate-*r/62.7%
metadata-eval62.7%
Simplified62.7%
Taylor expanded in x around 0 62.7%
(FPCore (x y) :precision binary64 (if (or (<= y -1.35e+50) (not (<= y 1.35e+94))) (- x (/ 2.0 x)) (- x y)))
double code(double x, double y) {
double tmp;
if ((y <= -1.35e+50) || !(y <= 1.35e+94)) {
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 <= (-1.35d+50)) .or. (.not. (y <= 1.35d+94))) 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 <= -1.35e+50) || !(y <= 1.35e+94)) {
tmp = x - (2.0 / x);
} else {
tmp = x - y;
}
return tmp;
}
def code(x, y): tmp = 0 if (y <= -1.35e+50) or not (y <= 1.35e+94): tmp = x - (2.0 / x) else: tmp = x - y return tmp
function code(x, y) tmp = 0.0 if ((y <= -1.35e+50) || !(y <= 1.35e+94)) 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 <= -1.35e+50) || ~((y <= 1.35e+94))) tmp = x - (2.0 / x); else tmp = x - y; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[y, -1.35e+50], N[Not[LessEqual[y, 1.35e+94]], $MachinePrecision]], N[(x - N[(2.0 / x), $MachinePrecision]), $MachinePrecision], N[(x - y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.35 \cdot 10^{+50} \lor \neg \left(y \leq 1.35 \cdot 10^{+94}\right):\\
\;\;\;\;x - \frac{2}{x}\\
\mathbf{else}:\\
\;\;\;\;x - y\\
\end{array}
\end{array}
if y < -1.35e50 or 1.3500000000000001e94 < y Initial program 99.9%
Taylor expanded in y around inf 86.2%
associate-*r/86.2%
metadata-eval86.2%
Simplified86.2%
if -1.35e50 < y < 1.3500000000000001e94Initial program 100.0%
Taylor expanded in y around 0 98.1%
neg-mul-198.1%
unsub-neg98.1%
Simplified98.1%
Final simplification93.2%
(FPCore (x y) :precision binary64 (if (<= x -1.7) x (if (<= x 1.4) (- x y) x)))
double code(double x, double y) {
double tmp;
if (x <= -1.7) {
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 <= (-1.7d0)) 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 <= -1.7) {
tmp = x;
} else if (x <= 1.4) {
tmp = x - y;
} else {
tmp = x;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -1.7: tmp = x elif x <= 1.4: tmp = x - y else: tmp = x return tmp
function code(x, y) tmp = 0.0 if (x <= -1.7) 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 <= -1.7) tmp = x; elseif (x <= 1.4) tmp = x - y; else tmp = x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -1.7], x, If[LessEqual[x, 1.4], N[(x - y), $MachinePrecision], x]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.7:\\
\;\;\;\;x\\
\mathbf{elif}\;x \leq 1.4:\\
\;\;\;\;x - y\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if x < -1.69999999999999996 or 1.3999999999999999 < x Initial program 100.0%
Taylor expanded in x around inf 99.5%
if -1.69999999999999996 < x < 1.3999999999999999Initial program 99.9%
Taylor expanded in y around 0 67.6%
neg-mul-167.6%
unsub-neg67.6%
Simplified67.6%
(FPCore (x y) :precision binary64 (if (<= x -2.4e-161) x (if (<= x 5.7e-97) (- y) x)))
double code(double x, double y) {
double tmp;
if (x <= -2.4e-161) {
tmp = x;
} else if (x <= 5.7e-97) {
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 <= (-2.4d-161)) then
tmp = x
else if (x <= 5.7d-97) then
tmp = -y
else
tmp = x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -2.4e-161) {
tmp = x;
} else if (x <= 5.7e-97) {
tmp = -y;
} else {
tmp = x;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -2.4e-161: tmp = x elif x <= 5.7e-97: tmp = -y else: tmp = x return tmp
function code(x, y) tmp = 0.0 if (x <= -2.4e-161) tmp = x; elseif (x <= 5.7e-97) tmp = Float64(-y); else tmp = x; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -2.4e-161) tmp = x; elseif (x <= 5.7e-97) tmp = -y; else tmp = x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -2.4e-161], x, If[LessEqual[x, 5.7e-97], (-y), x]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -2.4 \cdot 10^{-161}:\\
\;\;\;\;x\\
\mathbf{elif}\;x \leq 5.7 \cdot 10^{-97}:\\
\;\;\;\;-y\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if x < -2.39999999999999999e-161 or 5.7000000000000001e-97 < x Initial program 100.0%
Taylor expanded in x around inf 83.0%
if -2.39999999999999999e-161 < x < 5.7000000000000001e-97Initial program 99.9%
Taylor expanded in x around 0 68.4%
neg-mul-168.4%
Simplified68.4%
(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 62.5%
herbie shell --seed 2024163
(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)))))