
(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 3 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 (/ (* 0.5 (/ PI (+ b a))) (* b a)))
double code(double a, double b) {
return (0.5 * (((double) M_PI) / (b + a))) / (b * a);
}
public static double code(double a, double b) {
return (0.5 * (Math.PI / (b + a))) / (b * a);
}
def code(a, b): return (0.5 * (math.pi / (b + a))) / (b * a)
function code(a, b) return Float64(Float64(0.5 * Float64(pi / Float64(b + a))) / Float64(b * a)) end
function tmp = code(a, b) tmp = (0.5 * (pi / (b + a))) / (b * a); end
code[a_, b_] := N[(N[(0.5 * N[(Pi / N[(b + a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{0.5 \cdot \frac{\pi}{b + a}}{b \cdot a}
\end{array}
Initial program 77.3%
un-div-inv77.4%
difference-of-squares86.0%
associate-/r*86.7%
div-inv86.7%
metadata-eval86.7%
Applied egg-rr86.7%
associate-*l/99.6%
Applied egg-rr99.6%
associate-/l*99.7%
*-commutative99.7%
+-commutative99.7%
sub-neg99.7%
distribute-neg-frac99.7%
metadata-eval99.7%
Simplified99.7%
Taylor expanded in a around 0 99.7%
associate-/r*99.6%
Simplified99.6%
+-commutative99.6%
associate-/l/99.7%
div-inv99.7%
associate-/l*99.7%
Applied egg-rr99.7%
Final simplification99.7%
(FPCore (a b) :precision binary64 (* (/ (* 0.5 PI) a) (/ (/ 1.0 a) b)))
double code(double a, double b) {
return ((0.5 * ((double) M_PI)) / a) * ((1.0 / a) / b);
}
public static double code(double a, double b) {
return ((0.5 * Math.PI) / a) * ((1.0 / a) / b);
}
def code(a, b): return ((0.5 * math.pi) / a) * ((1.0 / a) / b)
function code(a, b) return Float64(Float64(Float64(0.5 * pi) / a) * Float64(Float64(1.0 / a) / b)) end
function tmp = code(a, b) tmp = ((0.5 * pi) / a) * ((1.0 / a) / b); end
code[a_, b_] := N[(N[(N[(0.5 * Pi), $MachinePrecision] / a), $MachinePrecision] * N[(N[(1.0 / a), $MachinePrecision] / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{0.5 \cdot \pi}{a} \cdot \frac{\frac{1}{a}}{b}
\end{array}
Initial program 77.3%
un-div-inv77.4%
difference-of-squares86.0%
associate-/r*86.7%
div-inv86.7%
metadata-eval86.7%
Applied egg-rr86.7%
associate-*l/99.6%
Applied egg-rr99.6%
associate-/l*99.7%
*-commutative99.7%
+-commutative99.7%
sub-neg99.7%
distribute-neg-frac99.7%
metadata-eval99.7%
Simplified99.7%
Taylor expanded in a around 0 99.7%
associate-/r*99.6%
Simplified99.6%
Taylor expanded in a around inf 64.2%
associate-*r/64.2%
Simplified64.2%
Final simplification64.2%
(FPCore (a b) :precision binary64 (/ (* 0.5 PI) (* (+ b a) (* b a))))
double code(double a, double b) {
return (0.5 * ((double) M_PI)) / ((b + a) * (b * a));
}
public static double code(double a, double b) {
return (0.5 * Math.PI) / ((b + a) * (b * a));
}
def code(a, b): return (0.5 * math.pi) / ((b + a) * (b * a))
function code(a, b) return Float64(Float64(0.5 * pi) / Float64(Float64(b + a) * Float64(b * a))) end
function tmp = code(a, b) tmp = (0.5 * pi) / ((b + a) * (b * a)); end
code[a_, b_] := N[(N[(0.5 * Pi), $MachinePrecision] / N[(N[(b + a), $MachinePrecision] * N[(b * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{0.5 \cdot \pi}{\left(b + a\right) \cdot \left(b \cdot a\right)}
\end{array}
Initial program 77.3%
un-div-inv77.4%
difference-of-squares86.0%
associate-/r*86.7%
div-inv86.7%
metadata-eval86.7%
Applied egg-rr86.7%
associate-*l/99.6%
Applied egg-rr99.6%
associate-/l*99.7%
*-commutative99.7%
+-commutative99.7%
sub-neg99.7%
distribute-neg-frac99.7%
metadata-eval99.7%
Simplified99.7%
Taylor expanded in a around 0 99.7%
associate-/r*99.6%
Simplified99.6%
+-commutative99.6%
associate-/l/99.7%
div-inv99.7%
associate-/l/98.9%
Applied egg-rr98.9%
Final simplification98.9%
herbie shell --seed 2024040
(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))))