
(FPCore (x) :precision binary64 (- (cbrt (+ x 1.0)) (cbrt x)))
double code(double x) {
return cbrt((x + 1.0)) - cbrt(x);
}
public static double code(double x) {
return Math.cbrt((x + 1.0)) - Math.cbrt(x);
}
function code(x) return Float64(cbrt(Float64(x + 1.0)) - cbrt(x)) end
code[x_] := N[(N[Power[N[(x + 1.0), $MachinePrecision], 1/3], $MachinePrecision] - N[Power[x, 1/3], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt[3]{x + 1} - \sqrt[3]{x}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 9 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (- (cbrt (+ x 1.0)) (cbrt x)))
double code(double x) {
return cbrt((x + 1.0)) - cbrt(x);
}
public static double code(double x) {
return Math.cbrt((x + 1.0)) - Math.cbrt(x);
}
function code(x) return Float64(cbrt(Float64(x + 1.0)) - cbrt(x)) end
code[x_] := N[(N[Power[N[(x + 1.0), $MachinePrecision], 1/3], $MachinePrecision] - N[Power[x, 1/3], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt[3]{x + 1} - \sqrt[3]{x}
\end{array}
(FPCore (x) :precision binary64 (let* ((t_0 (cbrt (sqrt (+ 1.0 x))))) (/ 1.0 (fma (cbrt x) (+ (cbrt x) (* t_0 t_0)) (pow (cbrt (+ 1.0 x)) 2.0)))))
double code(double x) {
double t_0 = cbrt(sqrt((1.0 + x)));
return 1.0 / fma(cbrt(x), (cbrt(x) + (t_0 * t_0)), pow(cbrt((1.0 + x)), 2.0));
}
function code(x) t_0 = cbrt(sqrt(Float64(1.0 + x))) return Float64(1.0 / fma(cbrt(x), Float64(cbrt(x) + Float64(t_0 * t_0)), (cbrt(Float64(1.0 + x)) ^ 2.0))) end
code[x_] := Block[{t$95$0 = N[Power[N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision], 1/3], $MachinePrecision]}, N[(1.0 / N[(N[Power[x, 1/3], $MachinePrecision] * N[(N[Power[x, 1/3], $MachinePrecision] + N[(t$95$0 * t$95$0), $MachinePrecision]), $MachinePrecision] + N[Power[N[Power[N[(1.0 + x), $MachinePrecision], 1/3], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt[3]{\sqrt{1 + x}}\\
\frac{1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x} + t\_0 \cdot t\_0, {\left(\sqrt[3]{1 + x}\right)}^{2}\right)}
\end{array}
\end{array}
Initial program 6.5%
pow1/37.7%
add-sqr-sqrt7.7%
pow27.7%
pow-pow7.7%
metadata-eval7.7%
Applied egg-rr7.7%
sqrt-pow27.7%
metadata-eval7.7%
pow1/36.5%
flip3--6.8%
div-inv6.8%
pow36.6%
add-cube-cbrt6.4%
rem-cube-cbrt9.3%
distribute-rgt-in9.3%
+-commutative9.3%
+-commutative9.3%
Applied egg-rr9.3%
associate-*r/9.3%
*-rgt-identity9.3%
+-commutative9.3%
associate--l+98.5%
+-inverses98.5%
metadata-eval98.5%
fma-define98.5%
+-commutative98.5%
+-commutative98.5%
Simplified98.5%
pow1/394.5%
add-sqr-sqrt94.5%
unpow-prod-down94.5%
Applied egg-rr94.5%
unpow1/395.8%
unpow1/398.7%
Simplified98.7%
(FPCore (x) :precision binary64 (let* ((t_0 (cbrt (sqrt (+ 1.0 x))))) (/ 1.0 (fma (cbrt x) (+ (cbrt x) (cbrt (+ 1.0 x))) (pow (* t_0 t_0) 2.0)))))
double code(double x) {
double t_0 = cbrt(sqrt((1.0 + x)));
return 1.0 / fma(cbrt(x), (cbrt(x) + cbrt((1.0 + x))), pow((t_0 * t_0), 2.0));
}
function code(x) t_0 = cbrt(sqrt(Float64(1.0 + x))) return Float64(1.0 / fma(cbrt(x), Float64(cbrt(x) + cbrt(Float64(1.0 + x))), (Float64(t_0 * t_0) ^ 2.0))) end
code[x_] := Block[{t$95$0 = N[Power[N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision], 1/3], $MachinePrecision]}, N[(1.0 / N[(N[Power[x, 1/3], $MachinePrecision] * N[(N[Power[x, 1/3], $MachinePrecision] + N[Power[N[(1.0 + x), $MachinePrecision], 1/3], $MachinePrecision]), $MachinePrecision] + N[Power[N[(t$95$0 * t$95$0), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt[3]{\sqrt{1 + x}}\\
\frac{1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x} + \sqrt[3]{1 + x}, {\left(t\_0 \cdot t\_0\right)}^{2}\right)}
\end{array}
\end{array}
Initial program 6.5%
pow1/37.7%
add-sqr-sqrt7.7%
pow27.7%
pow-pow7.7%
metadata-eval7.7%
Applied egg-rr7.7%
sqrt-pow27.7%
metadata-eval7.7%
pow1/36.5%
flip3--6.8%
div-inv6.8%
pow36.6%
add-cube-cbrt6.4%
rem-cube-cbrt9.3%
distribute-rgt-in9.3%
+-commutative9.3%
+-commutative9.3%
Applied egg-rr9.3%
associate-*r/9.3%
*-rgt-identity9.3%
+-commutative9.3%
associate--l+98.5%
+-inverses98.5%
metadata-eval98.5%
fma-define98.5%
+-commutative98.5%
+-commutative98.5%
Simplified98.5%
pow1/394.5%
add-sqr-sqrt94.5%
unpow-prod-down94.5%
Applied egg-rr93.1%
unpow1/395.8%
unpow1/398.7%
Simplified98.6%
(FPCore (x) :precision binary64 (let* ((t_0 (cbrt (+ 1.0 x)))) (/ 1.0 (+ (pow t_0 2.0) (* (cbrt x) (+ (cbrt x) t_0))))))
double code(double x) {
double t_0 = cbrt((1.0 + x));
return 1.0 / (pow(t_0, 2.0) + (cbrt(x) * (cbrt(x) + t_0)));
}
public static double code(double x) {
double t_0 = Math.cbrt((1.0 + x));
return 1.0 / (Math.pow(t_0, 2.0) + (Math.cbrt(x) * (Math.cbrt(x) + t_0)));
}
function code(x) t_0 = cbrt(Float64(1.0 + x)) return Float64(1.0 / Float64((t_0 ^ 2.0) + Float64(cbrt(x) * Float64(cbrt(x) + t_0)))) end
code[x_] := Block[{t$95$0 = N[Power[N[(1.0 + x), $MachinePrecision], 1/3], $MachinePrecision]}, N[(1.0 / N[(N[Power[t$95$0, 2.0], $MachinePrecision] + N[(N[Power[x, 1/3], $MachinePrecision] * N[(N[Power[x, 1/3], $MachinePrecision] + t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt[3]{1 + x}\\
\frac{1}{{t\_0}^{2} + \sqrt[3]{x} \cdot \left(\sqrt[3]{x} + t\_0\right)}
\end{array}
\end{array}
Initial program 6.5%
pow1/37.7%
add-sqr-sqrt7.7%
pow27.7%
pow-pow7.7%
metadata-eval7.7%
Applied egg-rr7.7%
sqrt-pow27.7%
metadata-eval7.7%
pow1/36.5%
flip3--6.8%
div-inv6.8%
pow36.6%
add-cube-cbrt6.4%
rem-cube-cbrt9.3%
distribute-rgt-in9.3%
+-commutative9.3%
+-commutative9.3%
Applied egg-rr9.3%
associate-*r/9.3%
*-rgt-identity9.3%
+-commutative9.3%
associate--l+98.5%
+-inverses98.5%
metadata-eval98.5%
fma-define98.5%
+-commutative98.5%
+-commutative98.5%
Simplified98.5%
fma-undefine98.5%
+-commutative98.5%
+-commutative98.5%
Applied egg-rr98.5%
Final simplification98.5%
(FPCore (x) :precision binary64 (/ (+ (* (cbrt x) 0.3333333333333333) (* (cbrt (/ 1.0 (pow x 2.0))) -0.1111111111111111)) x))
double code(double x) {
return ((cbrt(x) * 0.3333333333333333) + (cbrt((1.0 / pow(x, 2.0))) * -0.1111111111111111)) / x;
}
public static double code(double x) {
return ((Math.cbrt(x) * 0.3333333333333333) + (Math.cbrt((1.0 / Math.pow(x, 2.0))) * -0.1111111111111111)) / x;
}
function code(x) return Float64(Float64(Float64(cbrt(x) * 0.3333333333333333) + Float64(cbrt(Float64(1.0 / (x ^ 2.0))) * -0.1111111111111111)) / x) end
code[x_] := N[(N[(N[(N[Power[x, 1/3], $MachinePrecision] * 0.3333333333333333), $MachinePrecision] + N[(N[Power[N[(1.0 / N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision], 1/3], $MachinePrecision] * -0.1111111111111111), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{\sqrt[3]{x} \cdot 0.3333333333333333 + \sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111}{x}
\end{array}
Initial program 6.5%
add-sqr-sqrt6.1%
add-sqr-sqrt6.5%
difference-of-squares6.5%
pow1/36.5%
sqrt-pow16.5%
metadata-eval6.5%
pow1/36.5%
sqrt-pow16.5%
metadata-eval6.5%
pow1/34.1%
sqrt-pow14.1%
metadata-eval4.1%
pow1/36.5%
sqrt-pow16.6%
metadata-eval6.6%
Applied egg-rr6.6%
Taylor expanded in x around inf 98.3%
associate-+r+98.4%
+-commutative98.4%
distribute-rgt-out98.4%
metadata-eval98.4%
Simplified98.4%
Final simplification98.4%
(FPCore (x) :precision binary64 (if (<= x 1.55e+231) (* (/ (pow (cbrt x) 4.0) x) (/ 0.3333333333333333 x)) (/ 1.0 (+ 1.0 (* (cbrt x) (+ 1.0 (cbrt x)))))))
double code(double x) {
double tmp;
if (x <= 1.55e+231) {
tmp = (pow(cbrt(x), 4.0) / x) * (0.3333333333333333 / x);
} else {
tmp = 1.0 / (1.0 + (cbrt(x) * (1.0 + cbrt(x))));
}
return tmp;
}
public static double code(double x) {
double tmp;
if (x <= 1.55e+231) {
tmp = (Math.pow(Math.cbrt(x), 4.0) / x) * (0.3333333333333333 / x);
} else {
tmp = 1.0 / (1.0 + (Math.cbrt(x) * (1.0 + Math.cbrt(x))));
}
return tmp;
}
function code(x) tmp = 0.0 if (x <= 1.55e+231) tmp = Float64(Float64((cbrt(x) ^ 4.0) / x) * Float64(0.3333333333333333 / x)); else tmp = Float64(1.0 / Float64(1.0 + Float64(cbrt(x) * Float64(1.0 + cbrt(x))))); end return tmp end
code[x_] := If[LessEqual[x, 1.55e+231], N[(N[(N[Power[N[Power[x, 1/3], $MachinePrecision], 4.0], $MachinePrecision] / x), $MachinePrecision] * N[(0.3333333333333333 / x), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(1.0 + N[(N[Power[x, 1/3], $MachinePrecision] * N[(1.0 + N[Power[x, 1/3], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 1.55 \cdot 10^{+231}:\\
\;\;\;\;\frac{{\left(\sqrt[3]{x}\right)}^{4}}{x} \cdot \frac{0.3333333333333333}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{1 + \sqrt[3]{x} \cdot \left(1 + \sqrt[3]{x}\right)}\\
\end{array}
\end{array}
if x < 1.54999999999999995e231Initial program 7.0%
Taylor expanded in x around inf 32.8%
+-commutative32.8%
fma-define32.8%
Simplified32.8%
Taylor expanded in x around inf 31.6%
*-commutative31.6%
unpow231.6%
times-frac32.3%
pow1/330.2%
pow-pow87.9%
metadata-eval87.9%
metadata-eval87.9%
pow-pow87.9%
pow1/395.8%
Applied egg-rr95.8%
if 1.54999999999999995e231 < x Initial program 5.1%
flip3--5.1%
div-inv5.1%
rem-cube-cbrt3.3%
rem-cube-cbrt5.1%
+-commutative5.1%
distribute-rgt-out5.1%
+-commutative5.1%
fma-define5.1%
add-exp-log5.1%
Applied egg-rr5.1%
associate-*r/5.1%
*-rgt-identity5.1%
+-commutative5.1%
associate--l+92.2%
+-inverses92.2%
metadata-eval92.2%
+-commutative92.2%
exp-prod90.4%
Simplified90.4%
Taylor expanded in x around 0 17.7%
(FPCore (x) :precision binary64 (* (/ (pow (cbrt x) 4.0) x) (/ 0.3333333333333333 x)))
double code(double x) {
return (pow(cbrt(x), 4.0) / x) * (0.3333333333333333 / x);
}
public static double code(double x) {
return (Math.pow(Math.cbrt(x), 4.0) / x) * (0.3333333333333333 / x);
}
function code(x) return Float64(Float64((cbrt(x) ^ 4.0) / x) * Float64(0.3333333333333333 / x)) end
code[x_] := N[(N[(N[Power[N[Power[x, 1/3], $MachinePrecision], 4.0], $MachinePrecision] / x), $MachinePrecision] * N[(0.3333333333333333 / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{{\left(\sqrt[3]{x}\right)}^{4}}{x} \cdot \frac{0.3333333333333333}{x}
\end{array}
Initial program 6.5%
Taylor expanded in x around inf 25.3%
+-commutative25.3%
fma-define25.3%
Simplified25.3%
Taylor expanded in x around inf 24.4%
*-commutative24.4%
unpow224.4%
times-frac25.3%
pow1/323.7%
pow-pow68.1%
metadata-eval68.1%
metadata-eval68.1%
pow-pow68.1%
pow1/374.2%
Applied egg-rr74.2%
(FPCore (x) :precision binary64 (+ (cbrt x) (- 0.0 (pow x 0.3333333333333333))))
double code(double x) {
return cbrt(x) + (0.0 - pow(x, 0.3333333333333333));
}
public static double code(double x) {
return Math.cbrt(x) + (0.0 - Math.pow(x, 0.3333333333333333));
}
function code(x) return Float64(cbrt(x) + Float64(0.0 - (x ^ 0.3333333333333333))) end
code[x_] := N[(N[Power[x, 1/3], $MachinePrecision] + N[(0.0 - N[Power[x, 0.3333333333333333], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt[3]{x} + \left(0 - {x}^{0.3333333333333333}\right)
\end{array}
Initial program 6.5%
Taylor expanded in x around inf 4.1%
pow1/35.9%
Applied egg-rr5.9%
Final simplification5.9%
(FPCore (x) :precision binary64 (/ 0.3333333333333333 (cbrt (pow x 2.0))))
double code(double x) {
return 0.3333333333333333 / cbrt(pow(x, 2.0));
}
public static double code(double x) {
return 0.3333333333333333 / Math.cbrt(Math.pow(x, 2.0));
}
function code(x) return Float64(0.3333333333333333 / cbrt((x ^ 2.0))) end
code[x_] := N[(0.3333333333333333 / N[Power[N[Power[x, 2.0], $MachinePrecision], 1/3], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{0.3333333333333333}{\sqrt[3]{{x}^{2}}}
\end{array}
Initial program 6.5%
Taylor expanded in x around inf 25.3%
+-commutative25.3%
fma-define25.3%
Simplified25.3%
Taylor expanded in x around inf 24.4%
*-un-lft-identity24.4%
add-cbrt-cube13.8%
pow-sqr13.8%
metadata-eval13.8%
cbrt-prod23.5%
unpow223.5%
cbrt-prod23.4%
times-frac23.4%
pow1/321.9%
pow-pow23.2%
metadata-eval23.2%
metadata-eval23.2%
pow-pow23.2%
pow1/324.5%
Applied egg-rr54.2%
associate-*r/54.2%
*-commutative54.2%
associate-*r*54.1%
lft-mult-inverse55.4%
metadata-eval55.4%
Simplified55.4%
(FPCore (x) :precision binary64 (+ 1.0 (cbrt x)))
double code(double x) {
return 1.0 + cbrt(x);
}
public static double code(double x) {
return 1.0 + Math.cbrt(x);
}
function code(x) return Float64(1.0 + cbrt(x)) end
code[x_] := N[(1.0 + N[Power[x, 1/3], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
1 + \sqrt[3]{x}
\end{array}
Initial program 6.5%
Taylor expanded in x around 0 1.8%
sub-neg1.8%
rem-square-sqrt0.0%
fabs-sqr0.0%
rem-square-sqrt5.4%
fabs-neg5.4%
unpow1/35.4%
metadata-eval5.4%
pow-sqr5.4%
fabs-sqr5.4%
pow-sqr5.4%
metadata-eval5.4%
unpow1/35.4%
Simplified5.4%
(FPCore (x) :precision binary64 (let* ((t_0 (cbrt (+ x 1.0)))) (/ 1.0 (+ (+ (* t_0 t_0) (* (cbrt x) t_0)) (* (cbrt x) (cbrt x))))))
double code(double x) {
double t_0 = cbrt((x + 1.0));
return 1.0 / (((t_0 * t_0) + (cbrt(x) * t_0)) + (cbrt(x) * cbrt(x)));
}
public static double code(double x) {
double t_0 = Math.cbrt((x + 1.0));
return 1.0 / (((t_0 * t_0) + (Math.cbrt(x) * t_0)) + (Math.cbrt(x) * Math.cbrt(x)));
}
function code(x) t_0 = cbrt(Float64(x + 1.0)) return Float64(1.0 / Float64(Float64(Float64(t_0 * t_0) + Float64(cbrt(x) * t_0)) + Float64(cbrt(x) * cbrt(x)))) end
code[x_] := Block[{t$95$0 = N[Power[N[(x + 1.0), $MachinePrecision], 1/3], $MachinePrecision]}, N[(1.0 / N[(N[(N[(t$95$0 * t$95$0), $MachinePrecision] + N[(N[Power[x, 1/3], $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision] + N[(N[Power[x, 1/3], $MachinePrecision] * N[Power[x, 1/3], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt[3]{x + 1}\\
\frac{1}{\left(t\_0 \cdot t\_0 + \sqrt[3]{x} \cdot t\_0\right) + \sqrt[3]{x} \cdot \sqrt[3]{x}}
\end{array}
\end{array}
herbie shell --seed 2024086
(FPCore (x)
:name "2cbrt (problem 3.3.4)"
:precision binary64
:pre (and (> x 1.0) (< x 1e+308))
:alt
(/ 1.0 (+ (+ (* (cbrt (+ x 1.0)) (cbrt (+ x 1.0))) (* (cbrt x) (cbrt (+ x 1.0)))) (* (cbrt x) (cbrt x))))
(- (cbrt (+ x 1.0)) (cbrt x)))