
(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 73.1%
remove-double-neg73.1%
distribute-rgt-neg-out73.1%
distribute-frac-neg273.1%
neg-mul-173.1%
div-sub72.5%
distribute-lft-out--72.5%
neg-mul-172.5%
distribute-frac-neg272.5%
distribute-rgt-neg-out72.5%
remove-double-neg72.5%
cancel-sign-sub-inv72.5%
associate-/r*79.5%
associate-/r*79.5%
*-inverses79.5%
metadata-eval79.5%
metadata-eval79.5%
metadata-eval79.5%
metadata-eval79.5%
Simplified100.0%
Final simplification100.0%
(FPCore (x y)
:precision binary64
(if (or (<= x -2.75e-95)
(not (or (<= x 1.4e-156) (and (not (<= x 3.8e-98)) (<= x 6e-10)))))
(/ 0.5 y)
(/ -0.5 x)))
double code(double x, double y) {
double tmp;
if ((x <= -2.75e-95) || !((x <= 1.4e-156) || (!(x <= 3.8e-98) && (x <= 6e-10)))) {
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 <= (-2.75d-95)) .or. (.not. (x <= 1.4d-156) .or. (.not. (x <= 3.8d-98)) .and. (x <= 6d-10))) 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 <= -2.75e-95) || !((x <= 1.4e-156) || (!(x <= 3.8e-98) && (x <= 6e-10)))) {
tmp = 0.5 / y;
} else {
tmp = -0.5 / x;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -2.75e-95) or not ((x <= 1.4e-156) or (not (x <= 3.8e-98) and (x <= 6e-10))): tmp = 0.5 / y else: tmp = -0.5 / x return tmp
function code(x, y) tmp = 0.0 if ((x <= -2.75e-95) || !((x <= 1.4e-156) || (!(x <= 3.8e-98) && (x <= 6e-10)))) 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 <= -2.75e-95) || ~(((x <= 1.4e-156) || (~((x <= 3.8e-98)) && (x <= 6e-10))))) tmp = 0.5 / y; else tmp = -0.5 / x; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -2.75e-95], N[Not[Or[LessEqual[x, 1.4e-156], And[N[Not[LessEqual[x, 3.8e-98]], $MachinePrecision], LessEqual[x, 6e-10]]]], $MachinePrecision]], N[(0.5 / y), $MachinePrecision], N[(-0.5 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -2.75 \cdot 10^{-95} \lor \neg \left(x \leq 1.4 \cdot 10^{-156} \lor \neg \left(x \leq 3.8 \cdot 10^{-98}\right) \land x \leq 6 \cdot 10^{-10}\right):\\
\;\;\;\;\frac{0.5}{y}\\
\mathbf{else}:\\
\;\;\;\;\frac{-0.5}{x}\\
\end{array}
\end{array}
if x < -2.75000000000000001e-95 or 1.4000000000000001e-156 < x < 3.8000000000000003e-98 or 6e-10 < x Initial program 71.1%
remove-double-neg71.1%
distribute-rgt-neg-out71.1%
distribute-frac-neg271.1%
neg-mul-171.1%
div-sub70.7%
distribute-lft-out--70.7%
neg-mul-170.7%
distribute-frac-neg270.7%
distribute-rgt-neg-out70.7%
remove-double-neg70.7%
cancel-sign-sub-inv70.7%
associate-/r*81.5%
associate-/r*81.5%
*-inverses81.5%
metadata-eval81.5%
metadata-eval81.5%
metadata-eval81.5%
metadata-eval81.5%
Simplified100.0%
Taylor expanded in y around 0 74.9%
if -2.75000000000000001e-95 < x < 1.4000000000000001e-156 or 3.8000000000000003e-98 < x < 6e-10Initial program 76.5%
remove-double-neg76.5%
distribute-rgt-neg-out76.5%
distribute-frac-neg276.5%
neg-mul-176.5%
div-sub75.6%
distribute-lft-out--75.6%
neg-mul-175.6%
distribute-frac-neg275.6%
distribute-rgt-neg-out75.6%
remove-double-neg75.6%
cancel-sign-sub-inv75.6%
associate-/r*76.1%
associate-/r*76.1%
*-inverses76.1%
metadata-eval76.1%
metadata-eval76.1%
metadata-eval76.1%
metadata-eval76.1%
Simplified100.0%
Taylor expanded in y around inf 87.2%
Final simplification79.5%
(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 73.1%
remove-double-neg73.1%
distribute-rgt-neg-out73.1%
distribute-frac-neg273.1%
neg-mul-173.1%
div-sub72.5%
distribute-lft-out--72.5%
neg-mul-172.5%
distribute-frac-neg272.5%
distribute-rgt-neg-out72.5%
remove-double-neg72.5%
cancel-sign-sub-inv72.5%
associate-/r*79.5%
associate-/r*79.5%
*-inverses79.5%
metadata-eval79.5%
metadata-eval79.5%
metadata-eval79.5%
metadata-eval79.5%
Simplified100.0%
Taylor expanded in y around inf 49.6%
Final simplification49.6%
(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 2024089
(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)))