
(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 79.6%
remove-double-neg79.6%
distribute-rgt-neg-out79.6%
distribute-frac-neg279.6%
neg-mul-179.6%
div-sub79.0%
distribute-lft-out--79.0%
neg-mul-179.0%
distribute-frac-neg279.0%
distribute-rgt-neg-out79.0%
remove-double-neg79.0%
cancel-sign-sub-inv79.0%
associate-/r*83.4%
associate-/r*83.4%
*-inverses83.4%
metadata-eval83.4%
metadata-eval83.4%
*-lft-identity83.4%
distribute-rgt-neg-out83.4%
Simplified100.0%
(FPCore (x y)
:precision binary64
(if (or (<= y -3.9e+27)
(and (not (<= y -0.00355))
(or (<= y -0.000185)
(not
(or (<= y -1.7e-92)
(and (not (<= y -3.8e-110))
(or (<= y -2.05e-178)
(and (not (<= y -2e-178))
(<= y 3.4e-116)))))))))
(/ -0.5 x)
(/ 0.5 y)))
double code(double x, double y) {
double tmp;
if ((y <= -3.9e+27) || (!(y <= -0.00355) && ((y <= -0.000185) || !((y <= -1.7e-92) || (!(y <= -3.8e-110) && ((y <= -2.05e-178) || (!(y <= -2e-178) && (y <= 3.4e-116)))))))) {
tmp = -0.5 / x;
} else {
tmp = 0.5 / y;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if ((y <= (-3.9d+27)) .or. (.not. (y <= (-0.00355d0))) .and. (y <= (-0.000185d0)) .or. (.not. (y <= (-1.7d-92)) .or. (.not. (y <= (-3.8d-110))) .and. (y <= (-2.05d-178)) .or. (.not. (y <= (-2d-178))) .and. (y <= 3.4d-116))) then
tmp = (-0.5d0) / x
else
tmp = 0.5d0 / y
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((y <= -3.9e+27) || (!(y <= -0.00355) && ((y <= -0.000185) || !((y <= -1.7e-92) || (!(y <= -3.8e-110) && ((y <= -2.05e-178) || (!(y <= -2e-178) && (y <= 3.4e-116)))))))) {
tmp = -0.5 / x;
} else {
tmp = 0.5 / y;
}
return tmp;
}
def code(x, y): tmp = 0 if (y <= -3.9e+27) or (not (y <= -0.00355) and ((y <= -0.000185) or not ((y <= -1.7e-92) or (not (y <= -3.8e-110) and ((y <= -2.05e-178) or (not (y <= -2e-178) and (y <= 3.4e-116))))))): tmp = -0.5 / x else: tmp = 0.5 / y return tmp
function code(x, y) tmp = 0.0 if ((y <= -3.9e+27) || (!(y <= -0.00355) && ((y <= -0.000185) || !((y <= -1.7e-92) || (!(y <= -3.8e-110) && ((y <= -2.05e-178) || (!(y <= -2e-178) && (y <= 3.4e-116)))))))) tmp = Float64(-0.5 / x); else tmp = Float64(0.5 / y); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((y <= -3.9e+27) || (~((y <= -0.00355)) && ((y <= -0.000185) || ~(((y <= -1.7e-92) || (~((y <= -3.8e-110)) && ((y <= -2.05e-178) || (~((y <= -2e-178)) && (y <= 3.4e-116))))))))) tmp = -0.5 / x; else tmp = 0.5 / y; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[y, -3.9e+27], And[N[Not[LessEqual[y, -0.00355]], $MachinePrecision], Or[LessEqual[y, -0.000185], N[Not[Or[LessEqual[y, -1.7e-92], And[N[Not[LessEqual[y, -3.8e-110]], $MachinePrecision], Or[LessEqual[y, -2.05e-178], And[N[Not[LessEqual[y, -2e-178]], $MachinePrecision], LessEqual[y, 3.4e-116]]]]]], $MachinePrecision]]]], N[(-0.5 / x), $MachinePrecision], N[(0.5 / y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -3.9 \cdot 10^{+27} \lor \neg \left(y \leq -0.00355\right) \land \left(y \leq -0.000185 \lor \neg \left(y \leq -1.7 \cdot 10^{-92} \lor \neg \left(y \leq -3.8 \cdot 10^{-110}\right) \land \left(y \leq -2.05 \cdot 10^{-178} \lor \neg \left(y \leq -2 \cdot 10^{-178}\right) \land y \leq 3.4 \cdot 10^{-116}\right)\right)\right):\\
\;\;\;\;\frac{-0.5}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{0.5}{y}\\
\end{array}
\end{array}
if y < -3.8999999999999999e27 or -0.0035500000000000002 < y < -1.85e-4 or -1.7000000000000001e-92 < y < -3.7999999999999998e-110 or -2.05e-178 < y < -1.9999999999999999e-178 or 3.39999999999999992e-116 < y Initial program 78.7%
remove-double-neg78.7%
distribute-rgt-neg-out78.7%
distribute-frac-neg278.7%
neg-mul-178.7%
div-sub78.5%
distribute-lft-out--78.5%
neg-mul-178.5%
distribute-frac-neg278.5%
distribute-rgt-neg-out78.5%
remove-double-neg78.5%
cancel-sign-sub-inv78.5%
associate-/r*85.3%
associate-/r*85.3%
*-inverses85.3%
metadata-eval85.3%
metadata-eval85.3%
*-lft-identity85.3%
distribute-rgt-neg-out85.3%
Simplified100.0%
Taylor expanded in y around inf 74.2%
if -3.8999999999999999e27 < y < -0.0035500000000000002 or -1.85e-4 < y < -1.7000000000000001e-92 or -3.7999999999999998e-110 < y < -2.05e-178 or -1.9999999999999999e-178 < y < 3.39999999999999992e-116Initial program 80.8%
remove-double-neg80.8%
distribute-rgt-neg-out80.8%
distribute-frac-neg280.8%
neg-mul-180.8%
div-sub79.7%
distribute-lft-out--79.7%
neg-mul-179.7%
distribute-frac-neg279.7%
distribute-rgt-neg-out79.7%
remove-double-neg79.7%
cancel-sign-sub-inv79.7%
associate-/r*81.1%
associate-/r*81.1%
*-inverses81.1%
metadata-eval81.1%
metadata-eval81.1%
*-lft-identity81.1%
distribute-rgt-neg-out81.1%
Simplified100.0%
Taylor expanded in y around 0 85.4%
Final simplification79.2%
(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 79.6%
remove-double-neg79.6%
distribute-rgt-neg-out79.6%
distribute-frac-neg279.6%
neg-mul-179.6%
div-sub79.0%
distribute-lft-out--79.0%
neg-mul-179.0%
distribute-frac-neg279.0%
distribute-rgt-neg-out79.0%
remove-double-neg79.0%
cancel-sign-sub-inv79.0%
associate-/r*83.4%
associate-/r*83.4%
*-inverses83.4%
metadata-eval83.4%
metadata-eval83.4%
*-lft-identity83.4%
distribute-rgt-neg-out83.4%
Simplified100.0%
Taylor expanded in y around inf 48.5%
(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 2024107
(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)))