
(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 6 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) (+ (/ -1.0 b) (/ 1.0 a))) (+ b a)) (- b a)))
double code(double a, double b) {
return (((((double) M_PI) * 0.5) * ((-1.0 / b) + (1.0 / a))) / (b + a)) / (b - a);
}
public static double code(double a, double b) {
return (((Math.PI * 0.5) * ((-1.0 / b) + (1.0 / a))) / (b + a)) / (b - a);
}
def code(a, b): return (((math.pi * 0.5) * ((-1.0 / b) + (1.0 / a))) / (b + a)) / (b - a)
function code(a, b) return Float64(Float64(Float64(Float64(pi * 0.5) * Float64(Float64(-1.0 / b) + Float64(1.0 / a))) / Float64(b + a)) / Float64(b - a)) end
function tmp = code(a, b) tmp = (((pi * 0.5) * ((-1.0 / b) + (1.0 / a))) / (b + a)) / (b - a); end
code[a_, b_] := N[(N[(N[(N[(Pi * 0.5), $MachinePrecision] * N[(N[(-1.0 / b), $MachinePrecision] + N[(1.0 / a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b + a), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{\left(\pi \cdot 0.5\right) \cdot \left(\frac{-1}{b} + \frac{1}{a}\right)}{b + a}}{b - a}
\end{array}
Initial program 78.5%
associate-*l*78.5%
*-rgt-identity78.5%
associate-/l*78.5%
metadata-eval78.5%
associate-*l/78.4%
*-lft-identity78.4%
sub-neg78.4%
distribute-neg-frac78.4%
metadata-eval78.4%
Simplified78.4%
metadata-eval78.4%
div-inv78.4%
associate-*r/78.5%
*-commutative78.5%
difference-of-squares84.7%
associate-/r*99.6%
Applied egg-rr65.2%
+-commutative65.2%
add-sqr-sqrt29.5%
sqrt-unprod76.1%
frac-times76.1%
metadata-eval76.1%
metadata-eval76.1%
frac-times76.1%
sqrt-unprod53.7%
add-sqr-sqrt99.6%
div-inv99.6%
fma-define99.6%
Applied egg-rr99.6%
fma-undefine99.6%
neg-mul-199.6%
distribute-neg-frac99.6%
metadata-eval99.6%
Simplified99.6%
Final simplification99.6%
(FPCore (a b) :precision binary64 (* (/ (* PI 0.5) (+ b a)) (/ (+ (/ -1.0 b) (/ 1.0 a)) (- b a))))
double code(double a, double b) {
return ((((double) M_PI) * 0.5) / (b + a)) * (((-1.0 / b) + (1.0 / a)) / (b - a));
}
public static double code(double a, double b) {
return ((Math.PI * 0.5) / (b + a)) * (((-1.0 / b) + (1.0 / a)) / (b - a));
}
def code(a, b): return ((math.pi * 0.5) / (b + a)) * (((-1.0 / b) + (1.0 / a)) / (b - a))
function code(a, b) return Float64(Float64(Float64(pi * 0.5) / Float64(b + a)) * Float64(Float64(Float64(-1.0 / b) + Float64(1.0 / a)) / Float64(b - a))) end
function tmp = code(a, b) tmp = ((pi * 0.5) / (b + a)) * (((-1.0 / b) + (1.0 / a)) / (b - a)); end
code[a_, b_] := N[(N[(N[(Pi * 0.5), $MachinePrecision] / N[(b + a), $MachinePrecision]), $MachinePrecision] * N[(N[(N[(-1.0 / b), $MachinePrecision] + N[(1.0 / a), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{-1}{b} + \frac{1}{a}}{b - a}
\end{array}
Initial program 78.5%
un-div-inv78.5%
difference-of-squares84.7%
associate-/r*87.2%
div-inv87.2%
metadata-eval87.2%
Applied egg-rr87.2%
associate-*l/99.6%
associate-/l*99.6%
Applied egg-rr99.6%
associate-/l*99.6%
associate-*r/99.6%
*-commutative99.6%
+-commutative99.6%
sub-neg99.6%
distribute-neg-frac99.6%
metadata-eval99.6%
Simplified99.6%
Final simplification99.6%
(FPCore (a b) :precision binary64 (if (<= b 1.15e-170) (/ (/ (* PI -0.5) (* b a)) (- b a)) (* (/ PI (- a b)) (/ (/ -0.5 a) (+ b a)))))
double code(double a, double b) {
double tmp;
if (b <= 1.15e-170) {
tmp = ((((double) M_PI) * -0.5) / (b * a)) / (b - a);
} else {
tmp = (((double) M_PI) / (a - b)) * ((-0.5 / a) / (b + a));
}
return tmp;
}
public static double code(double a, double b) {
double tmp;
if (b <= 1.15e-170) {
tmp = ((Math.PI * -0.5) / (b * a)) / (b - a);
} else {
tmp = (Math.PI / (a - b)) * ((-0.5 / a) / (b + a));
}
return tmp;
}
def code(a, b): tmp = 0 if b <= 1.15e-170: tmp = ((math.pi * -0.5) / (b * a)) / (b - a) else: tmp = (math.pi / (a - b)) * ((-0.5 / a) / (b + a)) return tmp
function code(a, b) tmp = 0.0 if (b <= 1.15e-170) tmp = Float64(Float64(Float64(pi * -0.5) / Float64(b * a)) / Float64(b - a)); else tmp = Float64(Float64(pi / Float64(a - b)) * Float64(Float64(-0.5 / a) / Float64(b + a))); end return tmp end
function tmp_2 = code(a, b) tmp = 0.0; if (b <= 1.15e-170) tmp = ((pi * -0.5) / (b * a)) / (b - a); else tmp = (pi / (a - b)) * ((-0.5 / a) / (b + a)); end tmp_2 = tmp; end
code[a_, b_] := If[LessEqual[b, 1.15e-170], N[(N[(N[(Pi * -0.5), $MachinePrecision] / N[(b * a), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision], N[(N[(Pi / N[(a - b), $MachinePrecision]), $MachinePrecision] * N[(N[(-0.5 / a), $MachinePrecision] / N[(b + a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 1.15 \cdot 10^{-170}:\\
\;\;\;\;\frac{\frac{\pi \cdot -0.5}{b \cdot a}}{b - a}\\
\mathbf{else}:\\
\;\;\;\;\frac{\pi}{a - b} \cdot \frac{\frac{-0.5}{a}}{b + a}\\
\end{array}
\end{array}
if b < 1.14999999999999993e-170Initial program 74.6%
associate-*l*74.7%
*-rgt-identity74.7%
associate-/l*74.7%
metadata-eval74.7%
associate-*l/74.6%
*-lft-identity74.6%
sub-neg74.6%
distribute-neg-frac74.6%
metadata-eval74.6%
Simplified74.6%
metadata-eval74.6%
div-inv74.6%
associate-*r/74.6%
*-commutative74.6%
difference-of-squares84.0%
associate-/r*99.7%
Applied egg-rr58.4%
+-commutative58.4%
add-sqr-sqrt1.4%
sqrt-unprod75.9%
frac-times75.9%
metadata-eval75.9%
metadata-eval75.9%
frac-times75.9%
sqrt-unprod85.9%
add-sqr-sqrt99.7%
div-inv99.7%
fma-define99.7%
Applied egg-rr99.7%
fma-undefine99.7%
neg-mul-199.7%
distribute-neg-frac99.7%
metadata-eval99.7%
Simplified99.7%
Taylor expanded in b around 0 68.6%
associate-*r/68.6%
*-commutative68.6%
Simplified68.6%
if 1.14999999999999993e-170 < b Initial program 84.9%
un-div-inv84.9%
difference-of-squares85.9%
associate-/r*88.0%
div-inv88.0%
metadata-eval88.0%
Applied egg-rr88.0%
Taylor expanded in a around 0 66.5%
associate-/l/65.1%
*-commutative65.1%
*-commutative65.1%
frac-2neg65.1%
metadata-eval65.1%
frac-times65.1%
*-commutative65.1%
+-commutative65.1%
Applied egg-rr65.1%
*-commutative65.1%
*-commutative65.1%
neg-mul-165.1%
*-commutative65.1%
distribute-rgt-neg-in65.1%
metadata-eval65.1%
distribute-lft-neg-out65.1%
*-commutative65.1%
associate-*l*76.8%
distribute-lft-neg-in76.8%
sub-neg76.8%
distribute-neg-in76.8%
remove-double-neg76.8%
+-commutative76.8%
unsub-neg76.8%
Simplified76.8%
times-frac76.8%
+-commutative76.8%
*-commutative76.8%
Applied egg-rr76.8%
associate-/r*76.7%
Simplified76.7%
Final simplification71.6%
(FPCore (a b) :precision binary64 (if (<= b 1.65e-170) (/ (/ (* PI -0.5) (* b a)) (- b a)) (/ (* 0.5 (/ PI (* b a))) (- b a))))
double code(double a, double b) {
double tmp;
if (b <= 1.65e-170) {
tmp = ((((double) M_PI) * -0.5) / (b * a)) / (b - a);
} else {
tmp = (0.5 * (((double) M_PI) / (b * a))) / (b - a);
}
return tmp;
}
public static double code(double a, double b) {
double tmp;
if (b <= 1.65e-170) {
tmp = ((Math.PI * -0.5) / (b * a)) / (b - a);
} else {
tmp = (0.5 * (Math.PI / (b * a))) / (b - a);
}
return tmp;
}
def code(a, b): tmp = 0 if b <= 1.65e-170: tmp = ((math.pi * -0.5) / (b * a)) / (b - a) else: tmp = (0.5 * (math.pi / (b * a))) / (b - a) return tmp
function code(a, b) tmp = 0.0 if (b <= 1.65e-170) tmp = Float64(Float64(Float64(pi * -0.5) / Float64(b * a)) / Float64(b - a)); else tmp = Float64(Float64(0.5 * Float64(pi / Float64(b * a))) / Float64(b - a)); end return tmp end
function tmp_2 = code(a, b) tmp = 0.0; if (b <= 1.65e-170) tmp = ((pi * -0.5) / (b * a)) / (b - a); else tmp = (0.5 * (pi / (b * a))) / (b - a); end tmp_2 = tmp; end
code[a_, b_] := If[LessEqual[b, 1.65e-170], N[(N[(N[(Pi * -0.5), $MachinePrecision] / N[(b * a), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 * N[(Pi / N[(b * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 1.65 \cdot 10^{-170}:\\
\;\;\;\;\frac{\frac{\pi \cdot -0.5}{b \cdot a}}{b - a}\\
\mathbf{else}:\\
\;\;\;\;\frac{0.5 \cdot \frac{\pi}{b \cdot a}}{b - a}\\
\end{array}
\end{array}
if b < 1.65000000000000002e-170Initial program 74.6%
associate-*l*74.7%
*-rgt-identity74.7%
associate-/l*74.7%
metadata-eval74.7%
associate-*l/74.6%
*-lft-identity74.6%
sub-neg74.6%
distribute-neg-frac74.6%
metadata-eval74.6%
Simplified74.6%
metadata-eval74.6%
div-inv74.6%
associate-*r/74.6%
*-commutative74.6%
difference-of-squares84.0%
associate-/r*99.7%
Applied egg-rr58.4%
+-commutative58.4%
add-sqr-sqrt1.4%
sqrt-unprod75.9%
frac-times75.9%
metadata-eval75.9%
metadata-eval75.9%
frac-times75.9%
sqrt-unprod85.9%
add-sqr-sqrt99.7%
div-inv99.7%
fma-define99.7%
Applied egg-rr99.7%
fma-undefine99.7%
neg-mul-199.7%
distribute-neg-frac99.7%
metadata-eval99.7%
Simplified99.7%
Taylor expanded in b around 0 68.6%
associate-*r/68.6%
*-commutative68.6%
Simplified68.6%
if 1.65000000000000002e-170 < b Initial program 84.9%
associate-*l*85.0%
*-rgt-identity85.0%
associate-/l*85.0%
metadata-eval85.0%
associate-*l/84.8%
*-lft-identity84.8%
sub-neg84.8%
distribute-neg-frac84.8%
metadata-eval84.8%
Simplified84.8%
metadata-eval84.8%
div-inv84.8%
associate-*r/84.8%
*-commutative84.8%
difference-of-squares85.9%
associate-/r*99.6%
Applied egg-rr76.4%
Taylor expanded in a around 0 76.4%
Final simplification71.5%
(FPCore (a b) :precision binary64 (* (/ (* PI 0.5) (+ b a)) (/ 1.0 (* b a))))
double code(double a, double b) {
return ((((double) M_PI) * 0.5) / (b + a)) * (1.0 / (b * a));
}
public static double code(double a, double b) {
return ((Math.PI * 0.5) / (b + a)) * (1.0 / (b * a));
}
def code(a, b): return ((math.pi * 0.5) / (b + a)) * (1.0 / (b * a))
function code(a, b) return Float64(Float64(Float64(pi * 0.5) / Float64(b + a)) * Float64(1.0 / Float64(b * a))) end
function tmp = code(a, b) tmp = ((pi * 0.5) / (b + a)) * (1.0 / (b * a)); end
code[a_, b_] := N[(N[(N[(Pi * 0.5), $MachinePrecision] / N[(b + a), $MachinePrecision]), $MachinePrecision] * N[(1.0 / N[(b * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\pi \cdot 0.5}{b + a} \cdot \frac{1}{b \cdot a}
\end{array}
Initial program 78.5%
un-div-inv78.5%
difference-of-squares84.7%
associate-/r*87.2%
div-inv87.2%
metadata-eval87.2%
Applied egg-rr87.2%
associate-*l/99.6%
associate-/l*99.6%
Applied egg-rr99.6%
associate-/l*99.6%
associate-*r/99.6%
*-commutative99.6%
+-commutative99.6%
sub-neg99.6%
distribute-neg-frac99.6%
metadata-eval99.6%
Simplified99.6%
Taylor expanded in a around 0 99.6%
Final simplification99.6%
(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 \cdot a}}{b - a}
\end{array}
Initial program 78.5%
associate-*l*78.5%
*-rgt-identity78.5%
associate-/l*78.5%
metadata-eval78.5%
associate-*l/78.4%
*-lft-identity78.4%
sub-neg78.4%
distribute-neg-frac78.4%
metadata-eval78.4%
Simplified78.4%
metadata-eval78.4%
div-inv78.4%
associate-*r/78.5%
*-commutative78.5%
difference-of-squares84.7%
associate-/r*99.6%
Applied egg-rr65.2%
Taylor expanded in a around 0 65.2%
Final simplification65.2%
herbie shell --seed 2024044
(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))))