| Alternative 1 | |
|---|---|
| Accuracy | 99.4% |
| Cost | 32704 |
\[\sin b \cdot \frac{r}{\cos b \cdot \cos a - \sin b \cdot \sin a}
\]

(FPCore (r a b) :precision binary64 (/ (* r (sin b)) (cos (+ a b))))
(FPCore (r a b) :precision binary64 (/ (* r (sin b)) (fma (sin b) (- (sin a)) (* (cos b) (cos a)))))
double code(double r, double a, double b) {
return (r * sin(b)) / cos((a + b));
}
double code(double r, double a, double b) {
return (r * sin(b)) / fma(sin(b), -sin(a), (cos(b) * cos(a)));
}
function code(r, a, b) return Float64(Float64(r * sin(b)) / cos(Float64(a + b))) end
function code(r, a, b) return Float64(Float64(r * sin(b)) / fma(sin(b), Float64(-sin(a)), Float64(cos(b) * cos(a)))) end
code[r_, a_, b_] := N[(N[(r * N[Sin[b], $MachinePrecision]), $MachinePrecision] / N[Cos[N[(a + b), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
code[r_, a_, b_] := N[(N[(r * N[Sin[b], $MachinePrecision]), $MachinePrecision] / N[(N[Sin[b], $MachinePrecision] * (-N[Sin[a], $MachinePrecision]) + N[(N[Cos[b], $MachinePrecision] * N[Cos[a], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\frac{r \cdot \sin b}{\cos \left(a + b\right)}
\frac{r \cdot \sin b}{\mathsf{fma}\left(\sin b, -\sin a, \cos b \cdot \cos a\right)}
Herbie found 15 alternatives:
| Alternative | Accuracy | Speedup |
|---|
Initial program 77.8%
Simplified77.8%
[Start]77.8 | \[ \frac{r \cdot \sin b}{\cos \left(a + b\right)}
\] |
|---|---|
+-commutative [=>]77.8 | \[ \frac{r \cdot \sin b}{\cos \color{blue}{\left(b + a\right)}}
\] |
Applied egg-rr99.5%
[Start]77.8 | \[ \frac{r \cdot \sin b}{\cos \left(b + a\right)}
\] |
|---|---|
cos-sum [=>]99.5 | \[ \frac{r \cdot \sin b}{\color{blue}{\cos b \cdot \cos a - \sin b \cdot \sin a}}
\] |
Applied egg-rr99.6%
[Start]99.5 | \[ \frac{r \cdot \sin b}{\cos b \cdot \cos a - \sin b \cdot \sin a}
\] |
|---|---|
sub-neg [=>]99.5 | \[ \frac{r \cdot \sin b}{\color{blue}{\cos b \cdot \cos a + \left(-\sin b \cdot \sin a\right)}}
\] |
+-commutative [=>]99.5 | \[ \frac{r \cdot \sin b}{\color{blue}{\left(-\sin b \cdot \sin a\right) + \cos b \cdot \cos a}}
\] |
distribute-rgt-neg-in [=>]99.5 | \[ \frac{r \cdot \sin b}{\color{blue}{\sin b \cdot \left(-\sin a\right)} + \cos b \cdot \cos a}
\] |
fma-def [=>]99.6 | \[ \frac{r \cdot \sin b}{\color{blue}{\mathsf{fma}\left(\sin b, -\sin a, \cos b \cdot \cos a\right)}}
\] |
Final simplification99.6%
| Alternative 1 | |
|---|---|
| Accuracy | 99.4% |
| Cost | 32704 |
| Alternative 2 | |
|---|---|
| Accuracy | 99.5% |
| Cost | 32704 |
| Alternative 3 | |
|---|---|
| Accuracy | 99.5% |
| Cost | 32704 |
| Alternative 4 | |
|---|---|
| Accuracy | 99.4% |
| Cost | 32512 |
| Alternative 5 | |
|---|---|
| Accuracy | 77.9% |
| Cost | 26048 |
| Alternative 6 | |
|---|---|
| Accuracy | 76.8% |
| Cost | 13385 |
| Alternative 7 | |
|---|---|
| Accuracy | 76.8% |
| Cost | 13384 |
| Alternative 8 | |
|---|---|
| Accuracy | 77.0% |
| Cost | 13248 |
| Alternative 9 | |
|---|---|
| Accuracy | 77.0% |
| Cost | 13248 |
| Alternative 10 | |
|---|---|
| Accuracy | 55.0% |
| Cost | 13120 |
| Alternative 11 | |
|---|---|
| Accuracy | 55.2% |
| Cost | 6985 |
| Alternative 12 | |
|---|---|
| Accuracy | 55.2% |
| Cost | 6985 |
| Alternative 13 | |
|---|---|
| Accuracy | 38.0% |
| Cost | 6592 |
| Alternative 14 | |
|---|---|
| Accuracy | 34.0% |
| Cost | 192 |
herbie shell --seed 2023161
(FPCore (r a b)
:name "rsin A (should all be same)"
:precision binary64
(/ (* r (sin b)) (cos (+ a b))))