
(FPCore (a b) :precision binary64 (- (+ (pow (+ (* a a) (* b b)) 2.0) (* 4.0 (+ (* (* a a) (+ 1.0 a)) (* (* b b) (- 1.0 (* 3.0 a)))))) 1.0))
double code(double a, double b) {
return (pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0;
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = ((((a * a) + (b * b)) ** 2.0d0) + (4.0d0 * (((a * a) * (1.0d0 + a)) + ((b * b) * (1.0d0 - (3.0d0 * a)))))) - 1.0d0
end function
public static double code(double a, double b) {
return (Math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0;
}
def code(a, b): return (math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0
function code(a, b) return Float64(Float64((Float64(Float64(a * a) + Float64(b * b)) ^ 2.0) + Float64(4.0 * Float64(Float64(Float64(a * a) * Float64(1.0 + a)) + Float64(Float64(b * b) * Float64(1.0 - Float64(3.0 * a)))))) - 1.0) end
function tmp = code(a, b) tmp = ((((a * a) + (b * b)) ^ 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0; end
code[a_, b_] := N[(N[(N[Power[N[(N[(a * a), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision] + N[(4.0 * N[(N[(N[(a * a), $MachinePrecision] * N[(1.0 + a), $MachinePrecision]), $MachinePrecision] + N[(N[(b * b), $MachinePrecision] * N[(1.0 - N[(3.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision]
\begin{array}{l}
\\
\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 11 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (a b) :precision binary64 (- (+ (pow (+ (* a a) (* b b)) 2.0) (* 4.0 (+ (* (* a a) (+ 1.0 a)) (* (* b b) (- 1.0 (* 3.0 a)))))) 1.0))
double code(double a, double b) {
return (pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0;
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = ((((a * a) + (b * b)) ** 2.0d0) + (4.0d0 * (((a * a) * (1.0d0 + a)) + ((b * b) * (1.0d0 - (3.0d0 * a)))))) - 1.0d0
end function
public static double code(double a, double b) {
return (Math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0;
}
def code(a, b): return (math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0
function code(a, b) return Float64(Float64((Float64(Float64(a * a) + Float64(b * b)) ^ 2.0) + Float64(4.0 * Float64(Float64(Float64(a * a) * Float64(1.0 + a)) + Float64(Float64(b * b) * Float64(1.0 - Float64(3.0 * a)))))) - 1.0) end
function tmp = code(a, b) tmp = ((((a * a) + (b * b)) ^ 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0; end
code[a_, b_] := N[(N[(N[Power[N[(N[(a * a), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision] + N[(4.0 * N[(N[(N[(a * a), $MachinePrecision] * N[(1.0 + a), $MachinePrecision]), $MachinePrecision] + N[(N[(b * b), $MachinePrecision] * N[(1.0 - N[(3.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision]
\begin{array}{l}
\\
\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1
\end{array}
(FPCore (a b) :precision binary64 (if (<= (* b b) 50.0) (fma (* a (fma a (+ a 4.0) 4.0)) a -1.0) (+ -1.0 (+ (* 4.0 (* b b)) (/ (fma a a (* b b)) (/ 1.0 (* b b)))))))
double code(double a, double b) {
double tmp;
if ((b * b) <= 50.0) {
tmp = fma((a * fma(a, (a + 4.0), 4.0)), a, -1.0);
} else {
tmp = -1.0 + ((4.0 * (b * b)) + (fma(a, a, (b * b)) / (1.0 / (b * b))));
}
return tmp;
}
function code(a, b) tmp = 0.0 if (Float64(b * b) <= 50.0) tmp = fma(Float64(a * fma(a, Float64(a + 4.0), 4.0)), a, -1.0); else tmp = Float64(-1.0 + Float64(Float64(4.0 * Float64(b * b)) + Float64(fma(a, a, Float64(b * b)) / Float64(1.0 / Float64(b * b))))); end return tmp end
code[a_, b_] := If[LessEqual[N[(b * b), $MachinePrecision], 50.0], N[(N[(a * N[(a * N[(a + 4.0), $MachinePrecision] + 4.0), $MachinePrecision]), $MachinePrecision] * a + -1.0), $MachinePrecision], N[(-1.0 + N[(N[(4.0 * N[(b * b), $MachinePrecision]), $MachinePrecision] + N[(N[(a * a + N[(b * b), $MachinePrecision]), $MachinePrecision] / N[(1.0 / N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \cdot b \leq 50:\\
\;\;\;\;\mathsf{fma}\left(a \cdot \mathsf{fma}\left(a, a + 4, 4\right), a, -1\right)\\
\mathbf{else}:\\
\;\;\;\;-1 + \left(4 \cdot \left(b \cdot b\right) + \frac{\mathsf{fma}\left(a, a, b \cdot b\right)}{\frac{1}{b \cdot b}}\right)\\
\end{array}
\end{array}
if (*.f64 b b) < 50Initial program 84.6%
Taylor expanded in b around 0
sub-negN/A
+-commutativeN/A
metadata-evalN/A
pow-sqrN/A
*-commutativeN/A
associate-*r*N/A
distribute-rgt-outN/A
metadata-evalN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-fma.f64N/A
+-commutativeN/A
distribute-lft-inN/A
metadata-evalN/A
lower-fma.f6499.4
Applied rewrites99.4%
Applied rewrites99.5%
if 50 < (*.f64 b b) Initial program 62.8%
lift-pow.f64N/A
unpow2N/A
lift-+.f64N/A
flip-+N/A
clear-numN/A
un-div-invN/A
lower-/.f64N/A
lift-+.f64N/A
lift-*.f64N/A
lower-fma.f64N/A
clear-numN/A
flip-+N/A
lift-+.f64N/A
lower-/.f6462.7
lift-+.f64N/A
lift-*.f64N/A
lower-fma.f6462.7
Applied rewrites62.7%
Taylor expanded in a around 0
unpow2N/A
lower-*.f6499.9
Applied rewrites99.9%
Taylor expanded in a around 0
unpow2N/A
lower-*.f6499.9
Applied rewrites99.9%
Final simplification99.7%
(FPCore (a b) :precision binary64 (let* ((t_0 (fma a a (* b b)))) (+ (+ (/ t_0 (/ 1.0 t_0)) (* 4.0 (* b b))) -1.0)))
double code(double a, double b) {
double t_0 = fma(a, a, (b * b));
return ((t_0 / (1.0 / t_0)) + (4.0 * (b * b))) + -1.0;
}
function code(a, b) t_0 = fma(a, a, Float64(b * b)) return Float64(Float64(Float64(t_0 / Float64(1.0 / t_0)) + Float64(4.0 * Float64(b * b))) + -1.0) end
code[a_, b_] := Block[{t$95$0 = N[(a * a + N[(b * b), $MachinePrecision]), $MachinePrecision]}, N[(N[(N[(t$95$0 / N[(1.0 / t$95$0), $MachinePrecision]), $MachinePrecision] + N[(4.0 * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(a, a, b \cdot b\right)\\
\left(\frac{t\_0}{\frac{1}{t\_0}} + 4 \cdot \left(b \cdot b\right)\right) + -1
\end{array}
\end{array}
Initial program 73.2%
lift-pow.f64N/A
unpow2N/A
lift-+.f64N/A
flip-+N/A
clear-numN/A
un-div-invN/A
lower-/.f64N/A
lift-+.f64N/A
lift-*.f64N/A
lower-fma.f64N/A
clear-numN/A
flip-+N/A
lift-+.f64N/A
lower-/.f6473.2
lift-+.f64N/A
lift-*.f64N/A
lower-fma.f6473.2
Applied rewrites73.2%
Taylor expanded in a around 0
unpow2N/A
lower-*.f6499.0
Applied rewrites99.0%
Final simplification99.0%
herbie shell --seed 2024222
(FPCore (a b)
:name "Bouland and Aaronson, Equation (25)"
:precision binary64
(- (+ (pow (+ (* a a) (* b b)) 2.0) (* 4.0 (+ (* (* a a) (+ 1.0 a)) (* (* b b) (- 1.0 (* 3.0 a)))))) 1.0))