| Alternative 1 | |
|---|---|
| Accuracy | 93.8% |
| Cost | 7172 |
\[\begin{array}{l}
\mathbf{if}\;b \cdot b \leq 2 \cdot 10^{+40}:\\
\;\;\;\;{a}^{3} \cdot \left(a + -4\right) + -1\\
\mathbf{else}:\\
\;\;\;\;{b}^{4}\\
\end{array}
\]

(FPCore (a b) :precision binary64 (- (+ (pow (+ (* a a) (* b b)) 2.0) (* 4.0 (+ (* (* a a) (- 1.0 a)) (* (* b b) (+ 3.0 a))))) 1.0))
(FPCore (a b) :precision binary64 (+ (+ (pow (+ (* a a) (* b b)) 2.0) (* (* b b) 12.0)) -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) * (3.0 + a))))) - 1.0;
}
double code(double a, double b) {
return (pow(((a * a) + (b * b)), 2.0) + ((b * b) * 12.0)) + -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) * (3.0d0 + a))))) - 1.0d0
end function
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = ((((a * a) + (b * b)) ** 2.0d0) + ((b * b) * 12.0d0)) + (-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) * (3.0 + a))))) - 1.0;
}
public static double code(double a, double b) {
return (Math.pow(((a * a) + (b * b)), 2.0) + ((b * b) * 12.0)) + -1.0;
}
def code(a, b): return (math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 - a)) + ((b * b) * (3.0 + a))))) - 1.0
def code(a, b): return (math.pow(((a * a) + (b * b)), 2.0) + ((b * b) * 12.0)) + -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(3.0 + a))))) - 1.0) end
function code(a, b) return Float64(Float64((Float64(Float64(a * a) + Float64(b * b)) ^ 2.0) + Float64(Float64(b * b) * 12.0)) + -1.0) end
function tmp = code(a, b) tmp = ((((a * a) + (b * b)) ^ 2.0) + (4.0 * (((a * a) * (1.0 - a)) + ((b * b) * (3.0 + a))))) - 1.0; end
function tmp = code(a, b) tmp = ((((a * a) + (b * b)) ^ 2.0) + ((b * b) * 12.0)) + -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[(3.0 + a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision]
code[a_, b_] := N[(N[(N[Power[N[(N[(a * a), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision] + N[(N[(b * b), $MachinePrecision] * 12.0), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision]
\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(3 + a\right)\right)\right) - 1
\left({\left(a \cdot a + b \cdot b\right)}^{2} + \left(b \cdot b\right) \cdot 12\right) + -1
Herbie found 9 alternatives:
| Alternative | Accuracy | Speedup |
|---|
Results
Initial program 74.5%
Taylor expanded in a around 0 99.4%
Simplified99.4%
[Start]99.4 | \[ \left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(3 \cdot {b}^{2}\right)\right) - 1
\] |
|---|---|
*-commutative [=>]99.4 | \[ \left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \color{blue}{\left({b}^{2} \cdot 3\right)}\right) - 1
\] |
unpow2 [=>]99.4 | \[ \left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\color{blue}{\left(b \cdot b\right)} \cdot 3\right)\right) - 1
\] |
associate-*r* [<=]99.4 | \[ \left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \color{blue}{\left(b \cdot \left(b \cdot 3\right)\right)}\right) - 1
\] |
*-commutative [=>]99.4 | \[ \left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot \color{blue}{\left(3 \cdot b\right)}\right)\right) - 1
\] |
Taylor expanded in b around 0 99.4%
Simplified99.4%
[Start]99.4 | \[ \left({\left(a \cdot a + b \cdot b\right)}^{2} + 12 \cdot {b}^{2}\right) - 1
\] |
|---|---|
*-commutative [=>]99.4 | \[ \left({\left(a \cdot a + b \cdot b\right)}^{2} + \color{blue}{{b}^{2} \cdot 12}\right) - 1
\] |
unpow2 [=>]99.4 | \[ \left({\left(a \cdot a + b \cdot b\right)}^{2} + \color{blue}{\left(b \cdot b\right)} \cdot 12\right) - 1
\] |
Final simplification99.4%
| Alternative 1 | |
|---|---|
| Accuracy | 93.8% |
| Cost | 7172 |
| Alternative 2 | |
|---|---|
| Accuracy | 82.4% |
| Cost | 7048 |
| Alternative 3 | |
|---|---|
| Accuracy | 93.9% |
| Cost | 6920 |
| Alternative 4 | |
|---|---|
| Accuracy | 82.4% |
| Cost | 6792 |
| Alternative 5 | |
|---|---|
| Accuracy | 67.8% |
| Cost | 969 |
| Alternative 6 | |
|---|---|
| Accuracy | 71.8% |
| Cost | 968 |
| Alternative 7 | |
|---|---|
| Accuracy | 60.9% |
| Cost | 841 |
| Alternative 8 | |
|---|---|
| Accuracy | 51.1% |
| Cost | 448 |
herbie shell --seed 2023161
(FPCore (a b)
:name "Bouland and Aaronson, Equation (24)"
:precision binary64
(- (+ (pow (+ (* a a) (* b b)) 2.0) (* 4.0 (+ (* (* a a) (- 1.0 a)) (* (* b b) (+ 3.0 a))))) 1.0))