
(FPCore (x) :precision binary64 (/ (- 1.0 (cos x)) (* x x)))
double code(double x) {
return (1.0 - cos(x)) / (x * x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 - cos(x)) / (x * x)
end function
public static double code(double x) {
return (1.0 - Math.cos(x)) / (x * x);
}
def code(x): return (1.0 - math.cos(x)) / (x * x)
function code(x) return Float64(Float64(1.0 - cos(x)) / Float64(x * x)) end
function tmp = code(x) tmp = (1.0 - cos(x)) / (x * x); end
code[x_] := N[(N[(1.0 - N[Cos[x], $MachinePrecision]), $MachinePrecision] / N[(x * x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1 - \cos x}{x \cdot x}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (/ (- 1.0 (cos x)) (* x x)))
double code(double x) {
return (1.0 - cos(x)) / (x * x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 - cos(x)) / (x * x)
end function
public static double code(double x) {
return (1.0 - Math.cos(x)) / (x * x);
}
def code(x): return (1.0 - math.cos(x)) / (x * x)
function code(x) return Float64(Float64(1.0 - cos(x)) / Float64(x * x)) end
function tmp = code(x) tmp = (1.0 - cos(x)) / (x * x); end
code[x_] := N[(N[(1.0 - N[Cos[x], $MachinePrecision]), $MachinePrecision] / N[(x * x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1 - \cos x}{x \cdot x}
\end{array}
x_m = (fabs.f64 x)
(FPCore (x_m)
:precision binary64
(if (<= x_m 0.032)
(+
0.5
(*
(* x_m x_m)
(- (* (* x_m x_m) 0.001388888888888889) 0.041666666666666664)))
(/ (/ (- 1.0 (cos x_m)) x_m) x_m)))x_m = fabs(x);
double code(double x_m) {
double tmp;
if (x_m <= 0.032) {
tmp = 0.5 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889) - 0.041666666666666664));
} else {
tmp = ((1.0 - cos(x_m)) / x_m) / x_m;
}
return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
real(8) :: tmp
if (x_m <= 0.032d0) then
tmp = 0.5d0 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889d0) - 0.041666666666666664d0))
else
tmp = ((1.0d0 - cos(x_m)) / x_m) / x_m
end if
code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
double tmp;
if (x_m <= 0.032) {
tmp = 0.5 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889) - 0.041666666666666664));
} else {
tmp = ((1.0 - Math.cos(x_m)) / x_m) / x_m;
}
return tmp;
}
x_m = math.fabs(x) def code(x_m): tmp = 0 if x_m <= 0.032: tmp = 0.5 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889) - 0.041666666666666664)) else: tmp = ((1.0 - math.cos(x_m)) / x_m) / x_m return tmp
x_m = abs(x) function code(x_m) tmp = 0.0 if (x_m <= 0.032) tmp = Float64(0.5 + Float64(Float64(x_m * x_m) * Float64(Float64(Float64(x_m * x_m) * 0.001388888888888889) - 0.041666666666666664))); else tmp = Float64(Float64(Float64(1.0 - cos(x_m)) / x_m) / x_m); end return tmp end
x_m = abs(x); function tmp_2 = code(x_m) tmp = 0.0; if (x_m <= 0.032) tmp = 0.5 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889) - 0.041666666666666664)); else tmp = ((1.0 - cos(x_m)) / x_m) / x_m; end tmp_2 = tmp; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := If[LessEqual[x$95$m, 0.032], N[(0.5 + N[(N[(x$95$m * x$95$m), $MachinePrecision] * N[(N[(N[(x$95$m * x$95$m), $MachinePrecision] * 0.001388888888888889), $MachinePrecision] - 0.041666666666666664), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(1.0 - N[Cos[x$95$m], $MachinePrecision]), $MachinePrecision] / x$95$m), $MachinePrecision] / x$95$m), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
\begin{array}{l}
\mathbf{if}\;x\_m \leq 0.032:\\
\;\;\;\;0.5 + \left(x\_m \cdot x\_m\right) \cdot \left(\left(x\_m \cdot x\_m\right) \cdot 0.001388888888888889 - 0.041666666666666664\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{1 - \cos x\_m}{x\_m}}{x\_m}\\
\end{array}
\end{array}
if x < 0.032000000000000001Initial program 34.2%
Taylor expanded in x around 0 68.2%
pow268.2%
Applied egg-rr68.2%
pow268.2%
Applied egg-rr68.2%
if 0.032000000000000001 < x Initial program 98.3%
div-sub98.1%
pow298.1%
pow-flip98.2%
metadata-eval98.2%
div-inv98.2%
pow298.2%
pow-flip98.9%
metadata-eval98.9%
Applied egg-rr98.9%
*-un-lft-identity98.9%
distribute-rgt-out--99.1%
metadata-eval99.1%
pow-flip98.2%
associate-/r/98.3%
clear-num98.3%
pow298.3%
associate-/r*99.1%
Applied egg-rr99.1%
Final simplification75.9%
x_m = (fabs.f64 x)
(FPCore (x_m)
:precision binary64
(if (<= x_m 0.032)
(+
0.5
(*
(* x_m x_m)
(- (* (* x_m x_m) 0.001388888888888889) 0.041666666666666664)))
(/ (- 1.0 (cos x_m)) (* x_m x_m))))x_m = fabs(x);
double code(double x_m) {
double tmp;
if (x_m <= 0.032) {
tmp = 0.5 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889) - 0.041666666666666664));
} else {
tmp = (1.0 - cos(x_m)) / (x_m * x_m);
}
return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
real(8) :: tmp
if (x_m <= 0.032d0) then
tmp = 0.5d0 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889d0) - 0.041666666666666664d0))
else
tmp = (1.0d0 - cos(x_m)) / (x_m * x_m)
end if
code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
double tmp;
if (x_m <= 0.032) {
tmp = 0.5 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889) - 0.041666666666666664));
} else {
tmp = (1.0 - Math.cos(x_m)) / (x_m * x_m);
}
return tmp;
}
x_m = math.fabs(x) def code(x_m): tmp = 0 if x_m <= 0.032: tmp = 0.5 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889) - 0.041666666666666664)) else: tmp = (1.0 - math.cos(x_m)) / (x_m * x_m) return tmp
x_m = abs(x) function code(x_m) tmp = 0.0 if (x_m <= 0.032) tmp = Float64(0.5 + Float64(Float64(x_m * x_m) * Float64(Float64(Float64(x_m * x_m) * 0.001388888888888889) - 0.041666666666666664))); else tmp = Float64(Float64(1.0 - cos(x_m)) / Float64(x_m * x_m)); end return tmp end
x_m = abs(x); function tmp_2 = code(x_m) tmp = 0.0; if (x_m <= 0.032) tmp = 0.5 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889) - 0.041666666666666664)); else tmp = (1.0 - cos(x_m)) / (x_m * x_m); end tmp_2 = tmp; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := If[LessEqual[x$95$m, 0.032], N[(0.5 + N[(N[(x$95$m * x$95$m), $MachinePrecision] * N[(N[(N[(x$95$m * x$95$m), $MachinePrecision] * 0.001388888888888889), $MachinePrecision] - 0.041666666666666664), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 - N[Cos[x$95$m], $MachinePrecision]), $MachinePrecision] / N[(x$95$m * x$95$m), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
\begin{array}{l}
\mathbf{if}\;x\_m \leq 0.032:\\
\;\;\;\;0.5 + \left(x\_m \cdot x\_m\right) \cdot \left(\left(x\_m \cdot x\_m\right) \cdot 0.001388888888888889 - 0.041666666666666664\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{1 - \cos x\_m}{x\_m \cdot x\_m}\\
\end{array}
\end{array}
if x < 0.032000000000000001Initial program 34.2%
Taylor expanded in x around 0 68.2%
pow268.2%
Applied egg-rr68.2%
pow268.2%
Applied egg-rr68.2%
if 0.032000000000000001 < x Initial program 98.3%
Final simplification75.7%
x_m = (fabs.f64 x)
(FPCore (x_m)
:precision binary64
(if (<= x_m 7.5e+38)
(+
0.5
(*
(* x_m x_m)
(- (* (* x_m x_m) 0.001388888888888889) 0.041666666666666664)))
0.0))x_m = fabs(x);
double code(double x_m) {
double tmp;
if (x_m <= 7.5e+38) {
tmp = 0.5 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889) - 0.041666666666666664));
} else {
tmp = 0.0;
}
return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
real(8) :: tmp
if (x_m <= 7.5d+38) then
tmp = 0.5d0 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889d0) - 0.041666666666666664d0))
else
tmp = 0.0d0
end if
code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
double tmp;
if (x_m <= 7.5e+38) {
tmp = 0.5 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889) - 0.041666666666666664));
} else {
tmp = 0.0;
}
return tmp;
}
x_m = math.fabs(x) def code(x_m): tmp = 0 if x_m <= 7.5e+38: tmp = 0.5 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889) - 0.041666666666666664)) else: tmp = 0.0 return tmp
x_m = abs(x) function code(x_m) tmp = 0.0 if (x_m <= 7.5e+38) tmp = Float64(0.5 + Float64(Float64(x_m * x_m) * Float64(Float64(Float64(x_m * x_m) * 0.001388888888888889) - 0.041666666666666664))); else tmp = 0.0; end return tmp end
x_m = abs(x); function tmp_2 = code(x_m) tmp = 0.0; if (x_m <= 7.5e+38) tmp = 0.5 + ((x_m * x_m) * (((x_m * x_m) * 0.001388888888888889) - 0.041666666666666664)); else tmp = 0.0; end tmp_2 = tmp; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := If[LessEqual[x$95$m, 7.5e+38], N[(0.5 + N[(N[(x$95$m * x$95$m), $MachinePrecision] * N[(N[(N[(x$95$m * x$95$m), $MachinePrecision] * 0.001388888888888889), $MachinePrecision] - 0.041666666666666664), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.0]
\begin{array}{l}
x_m = \left|x\right|
\\
\begin{array}{l}
\mathbf{if}\;x\_m \leq 7.5 \cdot 10^{+38}:\\
\;\;\;\;0.5 + \left(x\_m \cdot x\_m\right) \cdot \left(\left(x\_m \cdot x\_m\right) \cdot 0.001388888888888889 - 0.041666666666666664\right)\\
\mathbf{else}:\\
\;\;\;\;0\\
\end{array}
\end{array}
if x < 7.4999999999999999e38Initial program 37.1%
Taylor expanded in x around 0 65.6%
pow265.6%
Applied egg-rr65.6%
pow265.6%
Applied egg-rr65.6%
if 7.4999999999999999e38 < x Initial program 98.2%
Taylor expanded in x around 0 59.9%
Taylor expanded in x around 0 59.9%
Final simplification64.4%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 (if (<= x_m 8e+76) 0.5 0.0))
x_m = fabs(x);
double code(double x_m) {
double tmp;
if (x_m <= 8e+76) {
tmp = 0.5;
} else {
tmp = 0.0;
}
return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
real(8) :: tmp
if (x_m <= 8d+76) then
tmp = 0.5d0
else
tmp = 0.0d0
end if
code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
double tmp;
if (x_m <= 8e+76) {
tmp = 0.5;
} else {
tmp = 0.0;
}
return tmp;
}
x_m = math.fabs(x) def code(x_m): tmp = 0 if x_m <= 8e+76: tmp = 0.5 else: tmp = 0.0 return tmp
x_m = abs(x) function code(x_m) tmp = 0.0 if (x_m <= 8e+76) tmp = 0.5; else tmp = 0.0; end return tmp end
x_m = abs(x); function tmp_2 = code(x_m) tmp = 0.0; if (x_m <= 8e+76) tmp = 0.5; else tmp = 0.0; end tmp_2 = tmp; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := If[LessEqual[x$95$m, 8e+76], 0.5, 0.0]
\begin{array}{l}
x_m = \left|x\right|
\\
\begin{array}{l}
\mathbf{if}\;x\_m \leq 8 \cdot 10^{+76}:\\
\;\;\;\;0.5\\
\mathbf{else}:\\
\;\;\;\;0\\
\end{array}
\end{array}
if x < 8.0000000000000004e76Initial program 39.2%
Taylor expanded in x around 0 63.7%
if 8.0000000000000004e76 < x Initial program 98.1%
Taylor expanded in x around 0 68.0%
Taylor expanded in x around 0 68.0%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 0.0)
x_m = fabs(x);
double code(double x_m) {
return 0.0;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
code = 0.0d0
end function
x_m = Math.abs(x);
public static double code(double x_m) {
return 0.0;
}
x_m = math.fabs(x) def code(x_m): return 0.0
x_m = abs(x) function code(x_m) return 0.0 end
x_m = abs(x); function tmp = code(x_m) tmp = 0.0; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := 0.0
\begin{array}{l}
x_m = \left|x\right|
\\
0
\end{array}
Initial program 50.2%
Taylor expanded in x around 0 24.7%
Taylor expanded in x around 0 25.4%
herbie shell --seed 2024161
(FPCore (x)
:name "cos2 (problem 3.4.1)"
:precision binary64
(/ (- 1.0 (cos x)) (* x x)))