
(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 10 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}
(FPCore (x) :precision binary64 (/ (* (/ (sin x) x) (tan (* x 0.5))) x))
double code(double x) {
return ((sin(x) / x) * tan((x * 0.5))) / x;
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((sin(x) / x) * tan((x * 0.5d0))) / x
end function
public static double code(double x) {
return ((Math.sin(x) / x) * Math.tan((x * 0.5))) / x;
}
def code(x): return ((math.sin(x) / x) * math.tan((x * 0.5))) / x
function code(x) return Float64(Float64(Float64(sin(x) / x) * tan(Float64(x * 0.5))) / x) end
function tmp = code(x) tmp = ((sin(x) / x) * tan((x * 0.5))) / x; end
code[x_] := N[(N[(N[(N[Sin[x], $MachinePrecision] / x), $MachinePrecision] * N[Tan[N[(x * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{\sin x}{x} \cdot \tan \left(x \cdot 0.5\right)}{x}
\end{array}
Initial program 55.0%
lift-/.f64N/A
lift--.f64N/A
flip--N/A
associate-/l/N/A
metadata-evalN/A
lift-cos.f64N/A
lift-cos.f64N/A
1-sub-cosN/A
times-fracN/A
lower-*.f64N/A
lower-/.f64N/A
lower-sin.f64N/A
lift-cos.f64N/A
hang-0p-tanN/A
lower-tan.f64N/A
lower-/.f6480.0
Applied rewrites80.0%
lift-*.f64N/A
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
associate-*l/N/A
lower-/.f64N/A
lower-*.f64N/A
lower-/.f6499.8
lift-/.f64N/A
div-invN/A
metadata-evalN/A
lower-*.f6499.8
Applied rewrites99.8%
(FPCore (x) :precision binary64 (/ (tan (* x 0.5)) (* x (/ x (sin x)))))
double code(double x) {
return tan((x * 0.5)) / (x * (x / sin(x)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = tan((x * 0.5d0)) / (x * (x / sin(x)))
end function
public static double code(double x) {
return Math.tan((x * 0.5)) / (x * (x / Math.sin(x)));
}
def code(x): return math.tan((x * 0.5)) / (x * (x / math.sin(x)))
function code(x) return Float64(tan(Float64(x * 0.5)) / Float64(x * Float64(x / sin(x)))) end
function tmp = code(x) tmp = tan((x * 0.5)) / (x * (x / sin(x))); end
code[x_] := N[(N[Tan[N[(x * 0.5), $MachinePrecision]], $MachinePrecision] / N[(x * N[(x / N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\tan \left(x \cdot 0.5\right)}{x \cdot \frac{x}{\sin x}}
\end{array}
Initial program 55.0%
lift-/.f64N/A
lift--.f64N/A
flip--N/A
associate-/l/N/A
metadata-evalN/A
lift-cos.f64N/A
lift-cos.f64N/A
1-sub-cosN/A
times-fracN/A
lower-*.f64N/A
lower-/.f64N/A
lower-sin.f64N/A
lift-cos.f64N/A
hang-0p-tanN/A
lower-tan.f64N/A
lower-/.f6480.0
Applied rewrites80.0%
lift-*.f64N/A
*-commutativeN/A
lift-/.f64N/A
clear-numN/A
un-div-invN/A
lower-/.f64N/A
lift-/.f64N/A
div-invN/A
metadata-evalN/A
lower-*.f64N/A
lift-*.f64N/A
associate-/l*N/A
lower-*.f64N/A
lower-/.f6499.1
Applied rewrites99.1%
(FPCore (x) :precision binary64 (if (<= x 0.032) (fma (* x x) (fma (* x x) 0.001388888888888889 -0.041666666666666664) 0.5) (/ (/ -1.0 (/ x (+ (cos x) -1.0))) x)))
double code(double x) {
double tmp;
if (x <= 0.032) {
tmp = fma((x * x), fma((x * x), 0.001388888888888889, -0.041666666666666664), 0.5);
} else {
tmp = (-1.0 / (x / (cos(x) + -1.0))) / x;
}
return tmp;
}
function code(x) tmp = 0.0 if (x <= 0.032) tmp = fma(Float64(x * x), fma(Float64(x * x), 0.001388888888888889, -0.041666666666666664), 0.5); else tmp = Float64(Float64(-1.0 / Float64(x / Float64(cos(x) + -1.0))) / x); end return tmp end
code[x_] := If[LessEqual[x, 0.032], N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * 0.001388888888888889 + -0.041666666666666664), $MachinePrecision] + 0.5), $MachinePrecision], N[(N[(-1.0 / N[(x / N[(N[Cos[x], $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.032:\\
\;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, 0.001388888888888889, -0.041666666666666664\right), 0.5\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{-1}{\frac{x}{\cos x + -1}}}{x}\\
\end{array}
\end{array}
if x < 0.032000000000000001Initial program 39.6%
Taylor expanded in x around 0
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
sub-negN/A
metadata-evalN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6463.4
Applied rewrites63.4%
if 0.032000000000000001 < x Initial program 96.7%
Applied rewrites99.3%
lift-/.f64N/A
clear-numN/A
lower-/.f64N/A
lower-/.f6499.3
Applied rewrites99.3%
Final simplification73.1%
(FPCore (x) :precision binary64 (if (<= x 0.032) (fma (* x x) (fma (* x x) 0.001388888888888889 -0.041666666666666664) 0.5) (* (+ (cos x) -1.0) (/ (/ -1.0 x) x))))
double code(double x) {
double tmp;
if (x <= 0.032) {
tmp = fma((x * x), fma((x * x), 0.001388888888888889, -0.041666666666666664), 0.5);
} else {
tmp = (cos(x) + -1.0) * ((-1.0 / x) / x);
}
return tmp;
}
function code(x) tmp = 0.0 if (x <= 0.032) tmp = fma(Float64(x * x), fma(Float64(x * x), 0.001388888888888889, -0.041666666666666664), 0.5); else tmp = Float64(Float64(cos(x) + -1.0) * Float64(Float64(-1.0 / x) / x)); end return tmp end
code[x_] := If[LessEqual[x, 0.032], N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * 0.001388888888888889 + -0.041666666666666664), $MachinePrecision] + 0.5), $MachinePrecision], N[(N[(N[Cos[x], $MachinePrecision] + -1.0), $MachinePrecision] * N[(N[(-1.0 / x), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.032:\\
\;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, 0.001388888888888889, -0.041666666666666664\right), 0.5\right)\\
\mathbf{else}:\\
\;\;\;\;\left(\cos x + -1\right) \cdot \frac{\frac{-1}{x}}{x}\\
\end{array}
\end{array}
if x < 0.032000000000000001Initial program 39.6%
Taylor expanded in x around 0
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
sub-negN/A
metadata-evalN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6463.4
Applied rewrites63.4%
if 0.032000000000000001 < x Initial program 96.7%
Applied rewrites99.3%
lift-/.f64N/A
clear-numN/A
associate-/r/N/A
lift-/.f64N/A
clear-numN/A
associate-/r/N/A
associate-*r*N/A
lower-*.f64N/A
lower-*.f64N/A
metadata-evalN/A
lift-neg.f64N/A
frac-2negN/A
lower-/.f64N/A
lower-/.f6499.2
Applied rewrites99.2%
lift-*.f64N/A
lift-/.f64N/A
un-div-invN/A
lower-/.f6499.3
Applied rewrites99.3%
Final simplification73.1%
(FPCore (x) :precision binary64 (if (<= x 0.032) (fma (* x x) (fma (* x x) 0.001388888888888889 -0.041666666666666664) 0.5) (/ (/ (- 1.0 (cos x)) x) x)))
double code(double x) {
double tmp;
if (x <= 0.032) {
tmp = fma((x * x), fma((x * x), 0.001388888888888889, -0.041666666666666664), 0.5);
} else {
tmp = ((1.0 - cos(x)) / x) / x;
}
return tmp;
}
function code(x) tmp = 0.0 if (x <= 0.032) tmp = fma(Float64(x * x), fma(Float64(x * x), 0.001388888888888889, -0.041666666666666664), 0.5); else tmp = Float64(Float64(Float64(1.0 - cos(x)) / x) / x); end return tmp end
code[x_] := If[LessEqual[x, 0.032], N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * 0.001388888888888889 + -0.041666666666666664), $MachinePrecision] + 0.5), $MachinePrecision], N[(N[(N[(1.0 - N[Cos[x], $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.032:\\
\;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, 0.001388888888888889, -0.041666666666666664\right), 0.5\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{1 - \cos x}{x}}{x}\\
\end{array}
\end{array}
if x < 0.032000000000000001Initial program 39.6%
Taylor expanded in x around 0
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
sub-negN/A
metadata-evalN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6463.4
Applied rewrites63.4%
if 0.032000000000000001 < x Initial program 96.7%
Applied rewrites99.3%
lift-/.f64N/A
lift-neg.f64N/A
distribute-frac-neg2N/A
distribute-frac-negN/A
lower-/.f64N/A
lift-/.f64N/A
distribute-neg-fracN/A
lift-+.f64N/A
+-commutativeN/A
distribute-neg-inN/A
metadata-evalN/A
sub-negN/A
lift-cos.f64N/A
lower-/.f64N/A
lift-cos.f64N/A
lower--.f6499.3
Applied rewrites99.3%
(FPCore (x) :precision binary64 (if (<= x 0.032) (fma (* x x) (fma (* x x) 0.001388888888888889 -0.041666666666666664) 0.5) (/ (- 1.0 (cos x)) (* x x))))
double code(double x) {
double tmp;
if (x <= 0.032) {
tmp = fma((x * x), fma((x * x), 0.001388888888888889, -0.041666666666666664), 0.5);
} else {
tmp = (1.0 - cos(x)) / (x * x);
}
return tmp;
}
function code(x) tmp = 0.0 if (x <= 0.032) tmp = fma(Float64(x * x), fma(Float64(x * x), 0.001388888888888889, -0.041666666666666664), 0.5); else tmp = Float64(Float64(1.0 - cos(x)) / Float64(x * x)); end return tmp end
code[x_] := If[LessEqual[x, 0.032], N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * 0.001388888888888889 + -0.041666666666666664), $MachinePrecision] + 0.5), $MachinePrecision], N[(N[(1.0 - N[Cos[x], $MachinePrecision]), $MachinePrecision] / N[(x * x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.032:\\
\;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, 0.001388888888888889, -0.041666666666666664\right), 0.5\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{1 - \cos x}{x \cdot x}\\
\end{array}
\end{array}
if x < 0.032000000000000001Initial program 39.6%
Taylor expanded in x around 0
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
sub-negN/A
metadata-evalN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6463.4
Applied rewrites63.4%
if 0.032000000000000001 < x Initial program 96.7%
(FPCore (x) :precision binary64 (if (<= x 7e+38) (fma (* x x) (fma (* x x) 0.001388888888888889 -0.041666666666666664) 0.5) (/ (- 1.0 1.0) (* x x))))
double code(double x) {
double tmp;
if (x <= 7e+38) {
tmp = fma((x * x), fma((x * x), 0.001388888888888889, -0.041666666666666664), 0.5);
} else {
tmp = (1.0 - 1.0) / (x * x);
}
return tmp;
}
function code(x) tmp = 0.0 if (x <= 7e+38) tmp = fma(Float64(x * x), fma(Float64(x * x), 0.001388888888888889, -0.041666666666666664), 0.5); else tmp = Float64(Float64(1.0 - 1.0) / Float64(x * x)); end return tmp end
code[x_] := If[LessEqual[x, 7e+38], N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * 0.001388888888888889 + -0.041666666666666664), $MachinePrecision] + 0.5), $MachinePrecision], N[(N[(1.0 - 1.0), $MachinePrecision] / N[(x * x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 7 \cdot 10^{+38}:\\
\;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, 0.001388888888888889, -0.041666666666666664\right), 0.5\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{1 - 1}{x \cdot x}\\
\end{array}
\end{array}
if x < 7.00000000000000003e38Initial program 41.1%
Taylor expanded in x around 0
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
sub-negN/A
metadata-evalN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6462.0
Applied rewrites62.0%
if 7.00000000000000003e38 < x Initial program 96.4%
Taylor expanded in x around 0
Applied rewrites56.1%
(FPCore (x) :precision binary64 (if (<= x 3.5) (fma -0.041666666666666664 (* x x) 0.5) (/ (- 1.0 1.0) (* x x))))
double code(double x) {
double tmp;
if (x <= 3.5) {
tmp = fma(-0.041666666666666664, (x * x), 0.5);
} else {
tmp = (1.0 - 1.0) / (x * x);
}
return tmp;
}
function code(x) tmp = 0.0 if (x <= 3.5) tmp = fma(-0.041666666666666664, Float64(x * x), 0.5); else tmp = Float64(Float64(1.0 - 1.0) / Float64(x * x)); end return tmp end
code[x_] := If[LessEqual[x, 3.5], N[(-0.041666666666666664 * N[(x * x), $MachinePrecision] + 0.5), $MachinePrecision], N[(N[(1.0 - 1.0), $MachinePrecision] / N[(x * x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 3.5:\\
\;\;\;\;\mathsf{fma}\left(-0.041666666666666664, x \cdot x, 0.5\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{1 - 1}{x \cdot x}\\
\end{array}
\end{array}
if x < 3.5Initial program 39.6%
Taylor expanded in x around 0
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6463.1
Applied rewrites63.1%
if 3.5 < x Initial program 96.7%
Taylor expanded in x around 0
Applied rewrites52.3%
(FPCore (x) :precision binary64 (/ 1.0 (fma x (* x 0.16666666666666666) 2.0)))
double code(double x) {
return 1.0 / fma(x, (x * 0.16666666666666666), 2.0);
}
function code(x) return Float64(1.0 / fma(x, Float64(x * 0.16666666666666666), 2.0)) end
code[x_] := N[(1.0 / N[(x * N[(x * 0.16666666666666666), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\mathsf{fma}\left(x, x \cdot 0.16666666666666666, 2\right)}
\end{array}
Initial program 55.0%
lift-/.f64N/A
lift--.f64N/A
div-subN/A
frac-subN/A
clear-numN/A
lower-/.f64N/A
lower-/.f64N/A
lift-*.f64N/A
associate-*l*N/A
lift-*.f64N/A
cube-unmultN/A
lower-*.f64N/A
cube-unmultN/A
lift-*.f64N/A
lower-*.f64N/A
*-lft-identityN/A
lower--.f64N/A
lift-*.f64N/A
associate-*l*N/A
lower-*.f64N/A
lower-*.f6417.3
Applied rewrites17.3%
Taylor expanded in x around 0
+-commutativeN/A
unpow2N/A
associate-*r*N/A
*-commutativeN/A
lower-fma.f64N/A
*-commutativeN/A
lower-*.f6476.3
Applied rewrites76.3%
(FPCore (x) :precision binary64 0.5)
double code(double x) {
return 0.5;
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.5d0
end function
public static double code(double x) {
return 0.5;
}
def code(x): return 0.5
function code(x) return 0.5 end
function tmp = code(x) tmp = 0.5; end
code[x_] := 0.5
\begin{array}{l}
\\
0.5
\end{array}
Initial program 55.0%
Taylor expanded in x around 0
Applied rewrites47.4%
herbie shell --seed 2024219
(FPCore (x)
:name "cos2 (problem 3.4.1)"
:precision binary64
(/ (- 1.0 (cos x)) (* x x)))