
(FPCore (x y) :precision binary64 (/ (- x y) (* (* x 2.0) y)))
double code(double x, double y) {
return (x - y) / ((x * 2.0) * y);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (x - y) / ((x * 2.0d0) * y)
end function
public static double code(double x, double y) {
return (x - y) / ((x * 2.0) * y);
}
def code(x, y): return (x - y) / ((x * 2.0) * y)
function code(x, y) return Float64(Float64(x - y) / Float64(Float64(x * 2.0) * y)) end
function tmp = code(x, y) tmp = (x - y) / ((x * 2.0) * y); end
code[x_, y_] := N[(N[(x - y), $MachinePrecision] / N[(N[(x * 2.0), $MachinePrecision] * y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{x - y}{\left(x \cdot 2\right) \cdot y}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 3 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (/ (- x y) (* (* x 2.0) y)))
double code(double x, double y) {
return (x - y) / ((x * 2.0) * y);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (x - y) / ((x * 2.0d0) * y)
end function
public static double code(double x, double y) {
return (x - y) / ((x * 2.0) * y);
}
def code(x, y): return (x - y) / ((x * 2.0) * y)
function code(x, y) return Float64(Float64(x - y) / Float64(Float64(x * 2.0) * y)) end
function tmp = code(x, y) tmp = (x - y) / ((x * 2.0) * y); end
code[x_, y_] := N[(N[(x - y), $MachinePrecision] / N[(N[(x * 2.0), $MachinePrecision] * y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{x - y}{\left(x \cdot 2\right) \cdot y}
\end{array}
(FPCore (x y) :precision binary64 (+ (/ 0.5 y) (/ -0.5 x)))
double code(double x, double y) {
return (0.5 / y) + (-0.5 / x);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (0.5d0 / y) + ((-0.5d0) / x)
end function
public static double code(double x, double y) {
return (0.5 / y) + (-0.5 / x);
}
def code(x, y): return (0.5 / y) + (-0.5 / x)
function code(x, y) return Float64(Float64(0.5 / y) + Float64(-0.5 / x)) end
function tmp = code(x, y) tmp = (0.5 / y) + (-0.5 / x); end
code[x_, y_] := N[(N[(0.5 / y), $MachinePrecision] + N[(-0.5 / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{0.5}{y} + \frac{-0.5}{x}
\end{array}
Initial program 78.6%
remove-double-neg78.6%
distribute-rgt-neg-out78.6%
distribute-frac-neg278.6%
neg-mul-178.6%
div-sub78.3%
distribute-lft-out--78.3%
neg-mul-178.3%
distribute-frac-neg278.3%
distribute-rgt-neg-out78.3%
remove-double-neg78.3%
cancel-sign-sub-inv78.3%
associate-/r*84.6%
associate-/r*84.6%
*-inverses84.6%
metadata-eval84.6%
metadata-eval84.6%
*-lft-identity84.6%
distribute-rgt-neg-out84.6%
Simplified100.0%
(FPCore (x y)
:precision binary64
(if (or (<= x -2850000000000.0)
(not
(or (<= x -5.9e-64) (and (not (<= x -6.6e-103)) (<= x 1.3e+16)))))
(/ 0.5 y)
(/ -0.5 x)))
double code(double x, double y) {
double tmp;
if ((x <= -2850000000000.0) || !((x <= -5.9e-64) || (!(x <= -6.6e-103) && (x <= 1.3e+16)))) {
tmp = 0.5 / y;
} else {
tmp = -0.5 / x;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if ((x <= (-2850000000000.0d0)) .or. (.not. (x <= (-5.9d-64)) .or. (.not. (x <= (-6.6d-103))) .and. (x <= 1.3d+16))) then
tmp = 0.5d0 / y
else
tmp = (-0.5d0) / x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((x <= -2850000000000.0) || !((x <= -5.9e-64) || (!(x <= -6.6e-103) && (x <= 1.3e+16)))) {
tmp = 0.5 / y;
} else {
tmp = -0.5 / x;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -2850000000000.0) or not ((x <= -5.9e-64) or (not (x <= -6.6e-103) and (x <= 1.3e+16))): tmp = 0.5 / y else: tmp = -0.5 / x return tmp
function code(x, y) tmp = 0.0 if ((x <= -2850000000000.0) || !((x <= -5.9e-64) || (!(x <= -6.6e-103) && (x <= 1.3e+16)))) tmp = Float64(0.5 / y); else tmp = Float64(-0.5 / x); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((x <= -2850000000000.0) || ~(((x <= -5.9e-64) || (~((x <= -6.6e-103)) && (x <= 1.3e+16))))) tmp = 0.5 / y; else tmp = -0.5 / x; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -2850000000000.0], N[Not[Or[LessEqual[x, -5.9e-64], And[N[Not[LessEqual[x, -6.6e-103]], $MachinePrecision], LessEqual[x, 1.3e+16]]]], $MachinePrecision]], N[(0.5 / y), $MachinePrecision], N[(-0.5 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -2850000000000 \lor \neg \left(x \leq -5.9 \cdot 10^{-64} \lor \neg \left(x \leq -6.6 \cdot 10^{-103}\right) \land x \leq 1.3 \cdot 10^{+16}\right):\\
\;\;\;\;\frac{0.5}{y}\\
\mathbf{else}:\\
\;\;\;\;\frac{-0.5}{x}\\
\end{array}
\end{array}
if x < -2.85e12 or -5.89999999999999995e-64 < x < -6.59999999999999979e-103 or 1.3e16 < x Initial program 79.6%
remove-double-neg79.6%
distribute-rgt-neg-out79.6%
distribute-frac-neg279.6%
neg-mul-179.6%
div-sub79.6%
distribute-lft-out--79.6%
neg-mul-179.6%
distribute-frac-neg279.6%
distribute-rgt-neg-out79.6%
remove-double-neg79.6%
cancel-sign-sub-inv79.6%
associate-/r*90.2%
associate-/r*90.2%
*-inverses90.2%
metadata-eval90.2%
metadata-eval90.2%
*-lft-identity90.2%
distribute-rgt-neg-out90.2%
Simplified100.0%
Taylor expanded in y around 0 81.6%
if -2.85e12 < x < -5.89999999999999995e-64 or -6.59999999999999979e-103 < x < 1.3e16Initial program 77.3%
remove-double-neg77.3%
distribute-rgt-neg-out77.3%
distribute-frac-neg277.3%
neg-mul-177.3%
div-sub76.6%
distribute-lft-out--76.6%
neg-mul-176.6%
distribute-frac-neg276.6%
distribute-rgt-neg-out76.6%
remove-double-neg76.6%
cancel-sign-sub-inv76.6%
associate-/r*77.2%
associate-/r*77.2%
*-inverses77.2%
metadata-eval77.2%
metadata-eval77.2%
*-lft-identity77.2%
distribute-rgt-neg-out77.2%
Simplified100.0%
Taylor expanded in y around inf 83.9%
Final simplification82.6%
(FPCore (x y) :precision binary64 (/ -0.5 x))
double code(double x, double y) {
return -0.5 / x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (-0.5d0) / x
end function
public static double code(double x, double y) {
return -0.5 / x;
}
def code(x, y): return -0.5 / x
function code(x, y) return Float64(-0.5 / x) end
function tmp = code(x, y) tmp = -0.5 / x; end
code[x_, y_] := N[(-0.5 / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{-0.5}{x}
\end{array}
Initial program 78.6%
remove-double-neg78.6%
distribute-rgt-neg-out78.6%
distribute-frac-neg278.6%
neg-mul-178.6%
div-sub78.3%
distribute-lft-out--78.3%
neg-mul-178.3%
distribute-frac-neg278.3%
distribute-rgt-neg-out78.3%
remove-double-neg78.3%
cancel-sign-sub-inv78.3%
associate-/r*84.6%
associate-/r*84.6%
*-inverses84.6%
metadata-eval84.6%
metadata-eval84.6%
*-lft-identity84.6%
distribute-rgt-neg-out84.6%
Simplified100.0%
Taylor expanded in y around inf 47.5%
(FPCore (x y) :precision binary64 (- (/ 0.5 y) (/ 0.5 x)))
double code(double x, double y) {
return (0.5 / y) - (0.5 / x);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (0.5d0 / y) - (0.5d0 / x)
end function
public static double code(double x, double y) {
return (0.5 / y) - (0.5 / x);
}
def code(x, y): return (0.5 / y) - (0.5 / x)
function code(x, y) return Float64(Float64(0.5 / y) - Float64(0.5 / x)) end
function tmp = code(x, y) tmp = (0.5 / y) - (0.5 / x); end
code[x_, y_] := N[(N[(0.5 / y), $MachinePrecision] - N[(0.5 / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{0.5}{y} - \frac{0.5}{x}
\end{array}
herbie shell --seed 2024110
(FPCore (x y)
:name "Linear.Projection:inversePerspective from linear-1.19.1.3, B"
:precision binary64
:alt
(- (/ 0.5 y) (/ 0.5 x))
(/ (- x y) (* (* x 2.0) y)))