Average Error: 0.1 → 0.1
Time: 4.4s
Precision: binary64
\[0 \leq e \land e \leq 1\]
\[\frac{e \cdot \sin v}{1 + e \cdot \cos v} \]
\[\frac{e}{\mathsf{fma}\left(e, \cos v, 1\right)} \cdot \sin v \]
\frac{e \cdot \sin v}{1 + e \cdot \cos v}
\frac{e}{\mathsf{fma}\left(e, \cos v, 1\right)} \cdot \sin v
(FPCore (e v) :precision binary64 (/ (* e (sin v)) (+ 1.0 (* e (cos v)))))
(FPCore (e v) :precision binary64 (* (/ e (fma e (cos v) 1.0)) (sin v)))
double code(double e, double v) {
	return (e * sin(v)) / (1.0 + (e * cos(v)));
}
double code(double e, double v) {
	return (e / fma(e, cos(v), 1.0)) * sin(v);
}

Error

Bits error versus e

Bits error versus v

Derivation

  1. Initial program 0.1

    \[\frac{e \cdot \sin v}{1 + e \cdot \cos v} \]
  2. Simplified0.1

    \[\leadsto \color{blue}{\frac{e \cdot \sin v}{\mathsf{fma}\left(e, \cos v, 1\right)}} \]
  3. Applied associate-/l*_binary640.3

    \[\leadsto \color{blue}{\frac{e}{\frac{\mathsf{fma}\left(e, \cos v, 1\right)}{\sin v}}} \]
  4. Applied associate-/r/_binary640.1

    \[\leadsto \color{blue}{\frac{e}{\mathsf{fma}\left(e, \cos v, 1\right)} \cdot \sin v} \]
  5. Final simplification0.1

    \[\leadsto \frac{e}{\mathsf{fma}\left(e, \cos v, 1\right)} \cdot \sin v \]

Reproduce

herbie shell --seed 2022077 
(FPCore (e v)
  :name "Trigonometry A"
  :precision binary64
  :pre (and (<= 0.0 e) (<= e 1.0))
  (/ (* e (sin v)) (+ 1.0 (* e (cos v)))))