
(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) (+ a b)) (* a b)))
double code(double a, double b) {
return ((0.5 * ((double) M_PI)) / (a + b)) / (a * b);
}
public static double code(double a, double b) {
return ((0.5 * Math.PI) / (a + b)) / (a * b);
}
def code(a, b): return ((0.5 * math.pi) / (a + b)) / (a * b)
function code(a, b) return Float64(Float64(Float64(0.5 * pi) / Float64(a + b)) / Float64(a * b)) end
function tmp = code(a, b) tmp = ((0.5 * pi) / (a + b)) / (a * b); end
code[a_, b_] := N[(N[(N[(0.5 * Pi), $MachinePrecision] / N[(a + b), $MachinePrecision]), $MachinePrecision] / N[(a * b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{0.5 \cdot \pi}{a + b}}{a \cdot b}
\end{array}
Initial program 78.7%
un-div-inv78.7%
difference-of-squares88.1%
associate-/r*89.4%
div-inv89.4%
metadata-eval89.4%
Applied egg-rr89.4%
Taylor expanded in a around inf 62.0%
Taylor expanded in b around 0 95.5%
neg-mul-195.5%
Simplified95.5%
associate-*l/93.4%
frac-2neg93.4%
*-commutative93.4%
frac-2neg93.4%
metadata-eval93.4%
frac-times92.4%
*-un-lft-identity92.4%
add-sqr-sqrt49.1%
sqrt-unprod55.9%
sqr-neg55.9%
sqrt-unprod14.5%
add-sqr-sqrt31.5%
add-sqr-sqrt17.1%
sqrt-unprod55.8%
sqr-neg55.8%
sqrt-unprod43.2%
add-sqr-sqrt92.4%
Applied egg-rr92.4%
*-commutative92.4%
associate-/r*93.5%
distribute-frac-neg293.5%
remove-double-neg93.5%
associate-/r*99.7%
*-commutative99.7%
+-commutative99.7%
*-commutative99.7%
Simplified99.7%
(FPCore (a b) :precision binary64 (* (/ 0.5 (+ a b)) (/ PI (* a b))))
double code(double a, double b) {
return (0.5 / (a + b)) * (((double) M_PI) / (a * b));
}
public static double code(double a, double b) {
return (0.5 / (a + b)) * (Math.PI / (a * b));
}
def code(a, b): return (0.5 / (a + b)) * (math.pi / (a * b))
function code(a, b) return Float64(Float64(0.5 / Float64(a + b)) * Float64(pi / Float64(a * b))) end
function tmp = code(a, b) tmp = (0.5 / (a + b)) * (pi / (a * b)); end
code[a_, b_] := N[(N[(0.5 / N[(a + b), $MachinePrecision]), $MachinePrecision] * N[(Pi / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{0.5}{a + b} \cdot \frac{\pi}{a \cdot b}
\end{array}
Initial program 78.7%
*-commutative78.7%
associate-*r*78.7%
associate-*r/78.7%
associate-*r*78.7%
*-rgt-identity78.7%
sub-neg78.7%
distribute-neg-frac78.7%
metadata-eval78.7%
Simplified78.7%
Taylor expanded in a around 0 56.4%
difference-of-squares63.4%
Applied egg-rr63.4%
times-frac70.6%
Applied egg-rr70.6%
Taylor expanded in a around 0 99.6%
Final simplification99.6%
(FPCore (a b) :precision binary64 (* PI (/ 0.5 (* (+ a b) (* a b)))))
double code(double a, double b) {
return ((double) M_PI) * (0.5 / ((a + b) * (a * b)));
}
public static double code(double a, double b) {
return Math.PI * (0.5 / ((a + b) * (a * b)));
}
def code(a, b): return math.pi * (0.5 / ((a + b) * (a * b)))
function code(a, b) return Float64(pi * Float64(0.5 / Float64(Float64(a + b) * Float64(a * b)))) end
function tmp = code(a, b) tmp = pi * (0.5 / ((a + b) * (a * b))); end
code[a_, b_] := N[(Pi * N[(0.5 / N[(N[(a + b), $MachinePrecision] * N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\pi \cdot \frac{0.5}{\left(a + b\right) \cdot \left(a \cdot b\right)}
\end{array}
Initial program 78.7%
un-div-inv78.7%
difference-of-squares88.1%
associate-/r*89.4%
div-inv89.4%
metadata-eval89.4%
Applied egg-rr89.4%
Taylor expanded in a around inf 62.0%
*-commutative62.0%
frac-2neg62.0%
metadata-eval62.0%
associate-/l/61.7%
*-commutative61.7%
frac-times61.8%
*-un-lft-identity61.8%
Applied egg-rr61.8%
associate-/l*61.7%
*-commutative61.7%
associate-*l*65.7%
+-commutative65.7%
*-commutative65.7%
distribute-lft-neg-out65.7%
distribute-rgt-neg-out65.7%
Simplified65.7%
Taylor expanded in b around 0 99.1%
herbie shell --seed 2024157
(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))))