
(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 6 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 (/ (/ (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(Float64(tan(Float64(x * 0.5)) / x) / Float64(x / sin(x))) end
function tmp = code(x) tmp = (tan((x * 0.5)) / x) / (x / sin(x)); end
code[x_] := N[(N[(N[Tan[N[(x * 0.5), $MachinePrecision]], $MachinePrecision] / x), $MachinePrecision] / N[(x / N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{\tan \left(x \cdot 0.5\right)}{x}}{\frac{x}{\sin x}}
\end{array}
Initial program 53.0%
flip--52.8%
div-inv52.8%
metadata-eval52.8%
pow252.8%
Applied egg-rr52.8%
associate-*r/52.8%
*-rgt-identity52.8%
Simplified52.8%
unpow252.8%
1-sub-cos76.2%
Applied egg-rr76.2%
associate-/l*76.2%
times-frac99.6%
hang-0p-tan99.8%
Applied egg-rr99.8%
*-commutative99.8%
clear-num99.8%
un-div-inv99.8%
div-inv99.8%
metadata-eval99.8%
Applied egg-rr99.8%
Final simplification99.8%
(FPCore (x) :precision binary64 (* (/ (sin x) x) (/ (tan (/ x 2.0)) x)))
double code(double x) {
return (sin(x) / x) * (tan((x / 2.0)) / x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (sin(x) / x) * (tan((x / 2.0d0)) / x)
end function
public static double code(double x) {
return (Math.sin(x) / x) * (Math.tan((x / 2.0)) / x);
}
def code(x): return (math.sin(x) / x) * (math.tan((x / 2.0)) / x)
function code(x) return Float64(Float64(sin(x) / x) * Float64(tan(Float64(x / 2.0)) / x)) end
function tmp = code(x) tmp = (sin(x) / x) * (tan((x / 2.0)) / x); end
code[x_] := N[(N[(N[Sin[x], $MachinePrecision] / x), $MachinePrecision] * N[(N[Tan[N[(x / 2.0), $MachinePrecision]], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\sin x}{x} \cdot \frac{\tan \left(\frac{x}{2}\right)}{x}
\end{array}
Initial program 53.0%
flip--52.8%
div-inv52.8%
metadata-eval52.8%
pow252.8%
Applied egg-rr52.8%
associate-*r/52.8%
*-rgt-identity52.8%
Simplified52.8%
unpow252.8%
1-sub-cos76.2%
Applied egg-rr76.2%
associate-/l*76.2%
times-frac99.6%
hang-0p-tan99.8%
Applied egg-rr99.8%
Final simplification99.8%
(FPCore (x) :precision binary64 (if (<= x 0.0058) (+ 0.5 (* -0.041666666666666664 (pow x 2.0))) (/ (/ (+ (cos x) -1.0) x) (- x))))
double code(double x) {
double tmp;
if (x <= 0.0058) {
tmp = 0.5 + (-0.041666666666666664 * pow(x, 2.0));
} else {
tmp = ((cos(x) + -1.0) / x) / -x;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= 0.0058d0) then
tmp = 0.5d0 + ((-0.041666666666666664d0) * (x ** 2.0d0))
else
tmp = ((cos(x) + (-1.0d0)) / x) / -x
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= 0.0058) {
tmp = 0.5 + (-0.041666666666666664 * Math.pow(x, 2.0));
} else {
tmp = ((Math.cos(x) + -1.0) / x) / -x;
}
return tmp;
}
def code(x): tmp = 0 if x <= 0.0058: tmp = 0.5 + (-0.041666666666666664 * math.pow(x, 2.0)) else: tmp = ((math.cos(x) + -1.0) / x) / -x return tmp
function code(x) tmp = 0.0 if (x <= 0.0058) tmp = Float64(0.5 + Float64(-0.041666666666666664 * (x ^ 2.0))); else tmp = Float64(Float64(Float64(cos(x) + -1.0) / x) / Float64(-x)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 0.0058) tmp = 0.5 + (-0.041666666666666664 * (x ^ 2.0)); else tmp = ((cos(x) + -1.0) / x) / -x; end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 0.0058], N[(0.5 + N[(-0.041666666666666664 * N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[Cos[x], $MachinePrecision] + -1.0), $MachinePrecision] / x), $MachinePrecision] / (-x)), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.0058:\\
\;\;\;\;0.5 + -0.041666666666666664 \cdot {x}^{2}\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{\cos x + -1}{x}}{-x}\\
\end{array}
\end{array}
if x < 0.0058Initial program 35.3%
Taylor expanded in x around 0 66.5%
if 0.0058 < x Initial program 99.0%
associate-/r*99.1%
div-inv99.1%
Applied egg-rr99.1%
div-sub98.8%
sub-neg98.8%
Applied egg-rr98.8%
sub-neg98.8%
Simplified98.8%
un-div-inv98.8%
frac-2neg98.8%
Applied egg-rr99.1%
Final simplification75.5%
(FPCore (x) :precision binary64 (if (<= x 0.0058) (+ 0.5 (* -0.041666666666666664 (pow x 2.0))) (/ (- 1.0 (cos x)) (* x x))))
double code(double x) {
double tmp;
if (x <= 0.0058) {
tmp = 0.5 + (-0.041666666666666664 * pow(x, 2.0));
} else {
tmp = (1.0 - cos(x)) / (x * x);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= 0.0058d0) then
tmp = 0.5d0 + ((-0.041666666666666664d0) * (x ** 2.0d0))
else
tmp = (1.0d0 - cos(x)) / (x * x)
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= 0.0058) {
tmp = 0.5 + (-0.041666666666666664 * Math.pow(x, 2.0));
} else {
tmp = (1.0 - Math.cos(x)) / (x * x);
}
return tmp;
}
def code(x): tmp = 0 if x <= 0.0058: tmp = 0.5 + (-0.041666666666666664 * math.pow(x, 2.0)) else: tmp = (1.0 - math.cos(x)) / (x * x) return tmp
function code(x) tmp = 0.0 if (x <= 0.0058) tmp = Float64(0.5 + Float64(-0.041666666666666664 * (x ^ 2.0))); else tmp = Float64(Float64(1.0 - cos(x)) / Float64(x * x)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 0.0058) tmp = 0.5 + (-0.041666666666666664 * (x ^ 2.0)); else tmp = (1.0 - cos(x)) / (x * x); end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 0.0058], N[(0.5 + N[(-0.041666666666666664 * N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $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 0.0058:\\
\;\;\;\;0.5 + -0.041666666666666664 \cdot {x}^{2}\\
\mathbf{else}:\\
\;\;\;\;\frac{1 - \cos x}{x \cdot x}\\
\end{array}
\end{array}
if x < 0.0058Initial program 35.3%
Taylor expanded in x around 0 66.5%
if 0.0058 < x Initial program 99.0%
Final simplification75.5%
(FPCore (x) :precision binary64 (if (<= x 9.2e+76) 0.5 (* (/ 1.0 x) (- (/ 1.0 x) (/ 1.0 x)))))
double code(double x) {
double tmp;
if (x <= 9.2e+76) {
tmp = 0.5;
} else {
tmp = (1.0 / x) * ((1.0 / x) - (1.0 / x));
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= 9.2d+76) then
tmp = 0.5d0
else
tmp = (1.0d0 / x) * ((1.0d0 / x) - (1.0d0 / x))
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= 9.2e+76) {
tmp = 0.5;
} else {
tmp = (1.0 / x) * ((1.0 / x) - (1.0 / x));
}
return tmp;
}
def code(x): tmp = 0 if x <= 9.2e+76: tmp = 0.5 else: tmp = (1.0 / x) * ((1.0 / x) - (1.0 / x)) return tmp
function code(x) tmp = 0.0 if (x <= 9.2e+76) tmp = 0.5; else tmp = Float64(Float64(1.0 / x) * Float64(Float64(1.0 / x) - Float64(1.0 / x))); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 9.2e+76) tmp = 0.5; else tmp = (1.0 / x) * ((1.0 / x) - (1.0 / x)); end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 9.2e+76], 0.5, N[(N[(1.0 / x), $MachinePrecision] * N[(N[(1.0 / x), $MachinePrecision] - N[(1.0 / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 9.2 \cdot 10^{+76}:\\
\;\;\;\;0.5\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{x} \cdot \left(\frac{1}{x} - \frac{1}{x}\right)\\
\end{array}
\end{array}
if x < 9.20000000000000005e76Initial program 40.8%
Taylor expanded in x around 0 61.6%
if 9.20000000000000005e76 < x Initial program 99.5%
associate-/r*99.6%
div-inv99.6%
Applied egg-rr99.6%
div-sub99.6%
sub-neg99.6%
Applied egg-rr99.6%
sub-neg99.6%
Simplified99.6%
Taylor expanded in x around 0 73.5%
Final simplification64.1%
(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 53.0%
Taylor expanded in x around 0 49.5%
Final simplification49.5%
herbie shell --seed 2024044
(FPCore (x)
:name "cos2 (problem 3.4.1)"
:precision binary64
(/ (- 1.0 (cos x)) (* x x)))