
(FPCore (a b) :precision binary64 (* (* (/ PI 2.0) (/ 1.0 (- (* b b) (* a a)))) (- (/ 1.0 a) (/ 1.0 b))))
double code(double a, double b) {
return ((((double) M_PI) / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
}
public static double code(double a, double b) {
return ((Math.PI / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
}
def code(a, b): return ((math.pi / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b))
function code(a, b) return Float64(Float64(Float64(pi / 2.0) * Float64(1.0 / Float64(Float64(b * b) - Float64(a * a)))) * Float64(Float64(1.0 / a) - Float64(1.0 / b))) end
function tmp = code(a, b) tmp = ((pi / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b)); end
code[a_, b_] := N[(N[(N[(Pi / 2.0), $MachinePrecision] * N[(1.0 / N[(N[(b * b), $MachinePrecision] - N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[(1.0 / a), $MachinePrecision] - N[(1.0 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (a b) :precision binary64 (* (* (/ PI 2.0) (/ 1.0 (- (* b b) (* a a)))) (- (/ 1.0 a) (/ 1.0 b))))
double code(double a, double b) {
return ((((double) M_PI) / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
}
public static double code(double a, double b) {
return ((Math.PI / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
}
def code(a, b): return ((math.pi / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b))
function code(a, b) return Float64(Float64(Float64(pi / 2.0) * Float64(1.0 / Float64(Float64(b * b) - Float64(a * a)))) * Float64(Float64(1.0 / a) - Float64(1.0 / b))) end
function tmp = code(a, b) tmp = ((pi / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b)); end
code[a_, b_] := N[(N[(N[(Pi / 2.0), $MachinePrecision] * N[(1.0 / N[(N[(b * b), $MachinePrecision] - N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[(1.0 / a), $MachinePrecision] - N[(1.0 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)
\end{array}
(FPCore (a b) :precision binary64 (/ (* (/ (* PI 0.5) (+ b a)) (- (/ 1.0 a) (/ 1.0 b))) (- b a)))
double code(double a, double b) {
return (((((double) M_PI) * 0.5) / (b + a)) * ((1.0 / a) - (1.0 / b))) / (b - a);
}
public static double code(double a, double b) {
return (((Math.PI * 0.5) / (b + a)) * ((1.0 / a) - (1.0 / b))) / (b - a);
}
def code(a, b): return (((math.pi * 0.5) / (b + a)) * ((1.0 / a) - (1.0 / b))) / (b - a)
function code(a, b) return Float64(Float64(Float64(Float64(pi * 0.5) / Float64(b + a)) * Float64(Float64(1.0 / a) - Float64(1.0 / b))) / Float64(b - a)) end
function tmp = code(a, b) tmp = (((pi * 0.5) / (b + a)) * ((1.0 / a) - (1.0 / b))) / (b - a); end
code[a_, b_] := N[(N[(N[(N[(Pi * 0.5), $MachinePrecision] / N[(b + a), $MachinePrecision]), $MachinePrecision] * N[(N[(1.0 / a), $MachinePrecision] - N[(1.0 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{\pi \cdot 0.5}{b + a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{b - a}
\end{array}
Initial program 77.1%
un-div-inv77.1%
difference-of-squares86.5%
associate-/r*86.5%
div-inv86.5%
metadata-eval86.5%
Applied egg-rr86.5%
associate-*l/99.7%
Applied egg-rr99.7%
Final simplification99.7%
(FPCore (a b) :precision binary64 (let* ((t_0 (/ 0.5 (* b a)))) (if (<= a -1.2e+109) (* (/ PI (- a)) t_0) (* (/ PI b) t_0))))
double code(double a, double b) {
double t_0 = 0.5 / (b * a);
double tmp;
if (a <= -1.2e+109) {
tmp = (((double) M_PI) / -a) * t_0;
} else {
tmp = (((double) M_PI) / b) * t_0;
}
return tmp;
}
public static double code(double a, double b) {
double t_0 = 0.5 / (b * a);
double tmp;
if (a <= -1.2e+109) {
tmp = (Math.PI / -a) * t_0;
} else {
tmp = (Math.PI / b) * t_0;
}
return tmp;
}
def code(a, b): t_0 = 0.5 / (b * a) tmp = 0 if a <= -1.2e+109: tmp = (math.pi / -a) * t_0 else: tmp = (math.pi / b) * t_0 return tmp
function code(a, b) t_0 = Float64(0.5 / Float64(b * a)) tmp = 0.0 if (a <= -1.2e+109) tmp = Float64(Float64(pi / Float64(-a)) * t_0); else tmp = Float64(Float64(pi / b) * t_0); end return tmp end
function tmp_2 = code(a, b) t_0 = 0.5 / (b * a); tmp = 0.0; if (a <= -1.2e+109) tmp = (pi / -a) * t_0; else tmp = (pi / b) * t_0; end tmp_2 = tmp; end
code[a_, b_] := Block[{t$95$0 = N[(0.5 / N[(b * a), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[a, -1.2e+109], N[(N[(Pi / (-a)), $MachinePrecision] * t$95$0), $MachinePrecision], N[(N[(Pi / b), $MachinePrecision] * t$95$0), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{0.5}{b \cdot a}\\
\mathbf{if}\;a \leq -1.2 \cdot 10^{+109}:\\
\;\;\;\;\frac{\pi}{-a} \cdot t\_0\\
\mathbf{else}:\\
\;\;\;\;\frac{\pi}{b} \cdot t\_0\\
\end{array}
\end{array}
if a < -1.19999999999999994e109Initial program 62.6%
associate-*l*62.5%
*-rgt-identity62.5%
associate-/l*62.5%
metadata-eval62.5%
associate-*l/62.6%
*-lft-identity62.6%
sub-neg62.6%
distribute-neg-frac62.6%
metadata-eval62.6%
Simplified62.6%
metadata-eval62.6%
div-inv62.6%
associate-*r/62.6%
*-commutative62.6%
difference-of-squares76.9%
associate-/r*99.8%
Applied egg-rr68.1%
Taylor expanded in a around 0 68.1%
associate-*r/68.1%
Simplified68.1%
*-un-lft-identity68.1%
associate-/l/68.1%
*-commutative68.1%
*-commutative68.1%
Applied egg-rr68.1%
*-lft-identity68.1%
times-frac68.1%
*-commutative68.1%
Simplified68.1%
Taylor expanded in b around 0 68.1%
neg-mul-168.1%
distribute-neg-frac268.1%
Simplified68.1%
if -1.19999999999999994e109 < a Initial program 80.5%
associate-*l*80.5%
*-rgt-identity80.5%
associate-/l*80.5%
metadata-eval80.5%
associate-*l/80.6%
*-lft-identity80.6%
sub-neg80.6%
distribute-neg-frac80.6%
metadata-eval80.6%
Simplified80.6%
metadata-eval80.6%
div-inv80.6%
associate-*r/80.6%
*-commutative80.6%
difference-of-squares88.8%
associate-/r*99.6%
Applied egg-rr63.6%
Taylor expanded in a around 0 63.6%
associate-*r/63.6%
Simplified63.6%
*-un-lft-identity63.6%
associate-/l/63.4%
*-commutative63.4%
*-commutative63.4%
Applied egg-rr63.4%
*-lft-identity63.4%
times-frac63.5%
*-commutative63.5%
Simplified63.5%
Taylor expanded in b around inf 67.9%
Final simplification67.9%
(FPCore (a b) :precision binary64 (* (/ 0.5 (+ b a)) (/ (/ PI b) a)))
double code(double a, double b) {
return (0.5 / (b + a)) * ((((double) M_PI) / b) / a);
}
public static double code(double a, double b) {
return (0.5 / (b + a)) * ((Math.PI / b) / a);
}
def code(a, b): return (0.5 / (b + a)) * ((math.pi / b) / a)
function code(a, b) return Float64(Float64(0.5 / Float64(b + a)) * Float64(Float64(pi / b) / a)) end
function tmp = code(a, b) tmp = (0.5 / (b + a)) * ((pi / b) / a); end
code[a_, b_] := N[(N[(0.5 / N[(b + a), $MachinePrecision]), $MachinePrecision] * N[(N[(Pi / b), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{a}
\end{array}
Initial program 77.1%
*-commutative77.1%
associate-*r*77.1%
associate-*r/77.1%
associate-*r*77.1%
*-rgt-identity77.1%
sub-neg77.1%
distribute-neg-frac77.1%
metadata-eval77.1%
Simplified77.1%
Taylor expanded in a around 0 54.5%
associate-*r/54.5%
Simplified54.5%
associate-/l*54.5%
difference-of-squares60.8%
times-frac65.8%
Applied egg-rr65.8%
Taylor expanded in a around 0 99.7%
associate-/l/99.6%
Simplified99.6%
Final simplification99.6%
(FPCore (a b) :precision binary64 (* (/ PI b) (/ 0.5 (* b a))))
double code(double a, double b) {
return (((double) M_PI) / b) * (0.5 / (b * a));
}
public static double code(double a, double b) {
return (Math.PI / b) * (0.5 / (b * a));
}
def code(a, b): return (math.pi / b) * (0.5 / (b * a))
function code(a, b) return Float64(Float64(pi / b) * Float64(0.5 / Float64(b * a))) end
function tmp = code(a, b) tmp = (pi / b) * (0.5 / (b * a)); end
code[a_, b_] := N[(N[(Pi / b), $MachinePrecision] * N[(0.5 / N[(b * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\pi}{b} \cdot \frac{0.5}{b \cdot a}
\end{array}
Initial program 77.1%
associate-*l*77.1%
*-rgt-identity77.1%
associate-/l*77.1%
metadata-eval77.1%
associate-*l/77.1%
*-lft-identity77.1%
sub-neg77.1%
distribute-neg-frac77.1%
metadata-eval77.1%
Simplified77.1%
metadata-eval77.1%
div-inv77.1%
associate-*r/77.1%
*-commutative77.1%
difference-of-squares86.5%
associate-/r*99.6%
Applied egg-rr64.4%
Taylor expanded in a around 0 64.4%
associate-*r/64.4%
Simplified64.4%
*-un-lft-identity64.4%
associate-/l/64.3%
*-commutative64.3%
*-commutative64.3%
Applied egg-rr64.3%
*-lft-identity64.3%
times-frac64.4%
*-commutative64.4%
Simplified64.4%
Taylor expanded in b around inf 63.4%
Final simplification63.4%
herbie shell --seed 2024053
(FPCore (a b)
:name "NMSE Section 6.1 mentioned, B"
:precision binary64
(* (* (/ PI 2.0) (/ 1.0 (- (* b b) (* a a)))) (- (/ 1.0 a) (/ 1.0 b))))