Average Error: 24.1 → 1.4
Time: 20.9s
Precision: binary64
Cost: 22340
\[\left(\alpha > -1 \land \beta > -1\right) \land i > 0\]
\[\frac{\frac{\frac{\left(\alpha + \beta\right) \cdot \left(\beta - \alpha\right)}{\left(\alpha + \beta\right) + 2 \cdot i}}{\left(\left(\alpha + \beta\right) + 2 \cdot i\right) + 2} + 1}{2} \]
\[\begin{array}{l} t_0 := \left(\alpha + \beta\right) + 2 \cdot i\\ \mathbf{if}\;\frac{\frac{\left(\alpha + \beta\right) \cdot \left(\beta - \alpha\right)}{t_0}}{2 + t_0} \leq -0.999998:\\ \;\;\;\;0.5 \cdot \frac{\left(2 + \beta \cdot 2\right) + i \cdot 4}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\frac{\alpha + \beta}{\beta + \mathsf{fma}\left(2, i, \alpha\right)}, \frac{\beta - \alpha}{\alpha + \left(\beta + \mathsf{fma}\left(2, i, 2\right)\right)}, 1\right)}{2}\\ \end{array} \]
(FPCore (alpha beta i)
 :precision binary64
 (/
  (+
   (/
    (/ (* (+ alpha beta) (- beta alpha)) (+ (+ alpha beta) (* 2.0 i)))
    (+ (+ (+ alpha beta) (* 2.0 i)) 2.0))
   1.0)
  2.0))
(FPCore (alpha beta i)
 :precision binary64
 (let* ((t_0 (+ (+ alpha beta) (* 2.0 i))))
   (if (<= (/ (/ (* (+ alpha beta) (- beta alpha)) t_0) (+ 2.0 t_0)) -0.999998)
     (* 0.5 (/ (+ (+ 2.0 (* beta 2.0)) (* i 4.0)) alpha))
     (/
      (fma
       (/ (+ alpha beta) (+ beta (fma 2.0 i alpha)))
       (/ (- beta alpha) (+ alpha (+ beta (fma 2.0 i 2.0))))
       1.0)
      2.0))))
double code(double alpha, double beta, double i) {
	return (((((alpha + beta) * (beta - alpha)) / ((alpha + beta) + (2.0 * i))) / (((alpha + beta) + (2.0 * i)) + 2.0)) + 1.0) / 2.0;
}
double code(double alpha, double beta, double i) {
	double t_0 = (alpha + beta) + (2.0 * i);
	double tmp;
	if (((((alpha + beta) * (beta - alpha)) / t_0) / (2.0 + t_0)) <= -0.999998) {
		tmp = 0.5 * (((2.0 + (beta * 2.0)) + (i * 4.0)) / alpha);
	} else {
		tmp = fma(((alpha + beta) / (beta + fma(2.0, i, alpha))), ((beta - alpha) / (alpha + (beta + fma(2.0, i, 2.0)))), 1.0) / 2.0;
	}
	return tmp;
}
function code(alpha, beta, i)
	return Float64(Float64(Float64(Float64(Float64(Float64(alpha + beta) * Float64(beta - alpha)) / Float64(Float64(alpha + beta) + Float64(2.0 * i))) / Float64(Float64(Float64(alpha + beta) + Float64(2.0 * i)) + 2.0)) + 1.0) / 2.0)
end
function code(alpha, beta, i)
	t_0 = Float64(Float64(alpha + beta) + Float64(2.0 * i))
	tmp = 0.0
	if (Float64(Float64(Float64(Float64(alpha + beta) * Float64(beta - alpha)) / t_0) / Float64(2.0 + t_0)) <= -0.999998)
		tmp = Float64(0.5 * Float64(Float64(Float64(2.0 + Float64(beta * 2.0)) + Float64(i * 4.0)) / alpha));
	else
		tmp = Float64(fma(Float64(Float64(alpha + beta) / Float64(beta + fma(2.0, i, alpha))), Float64(Float64(beta - alpha) / Float64(alpha + Float64(beta + fma(2.0, i, 2.0)))), 1.0) / 2.0);
	end
	return tmp
end
code[alpha_, beta_, i_] := N[(N[(N[(N[(N[(N[(alpha + beta), $MachinePrecision] * N[(beta - alpha), $MachinePrecision]), $MachinePrecision] / N[(N[(alpha + beta), $MachinePrecision] + N[(2.0 * i), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(N[(alpha + beta), $MachinePrecision] + N[(2.0 * i), $MachinePrecision]), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision] / 2.0), $MachinePrecision]
code[alpha_, beta_, i_] := Block[{t$95$0 = N[(N[(alpha + beta), $MachinePrecision] + N[(2.0 * i), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(N[(alpha + beta), $MachinePrecision] * N[(beta - alpha), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision] / N[(2.0 + t$95$0), $MachinePrecision]), $MachinePrecision], -0.999998], N[(0.5 * N[(N[(N[(2.0 + N[(beta * 2.0), $MachinePrecision]), $MachinePrecision] + N[(i * 4.0), $MachinePrecision]), $MachinePrecision] / alpha), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(alpha + beta), $MachinePrecision] / N[(beta + N[(2.0 * i + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[(beta - alpha), $MachinePrecision] / N[(alpha + N[(beta + N[(2.0 * i + 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision] / 2.0), $MachinePrecision]]]
\frac{\frac{\frac{\left(\alpha + \beta\right) \cdot \left(\beta - \alpha\right)}{\left(\alpha + \beta\right) + 2 \cdot i}}{\left(\left(\alpha + \beta\right) + 2 \cdot i\right) + 2} + 1}{2}
\begin{array}{l}
t_0 := \left(\alpha + \beta\right) + 2 \cdot i\\
\mathbf{if}\;\frac{\frac{\left(\alpha + \beta\right) \cdot \left(\beta - \alpha\right)}{t_0}}{2 + t_0} \leq -0.999998:\\
\;\;\;\;0.5 \cdot \frac{\left(2 + \beta \cdot 2\right) + i \cdot 4}{\alpha}\\

\mathbf{else}:\\
\;\;\;\;\frac{\mathsf{fma}\left(\frac{\alpha + \beta}{\beta + \mathsf{fma}\left(2, i, \alpha\right)}, \frac{\beta - \alpha}{\alpha + \left(\beta + \mathsf{fma}\left(2, i, 2\right)\right)}, 1\right)}{2}\\


\end{array}

Error

Derivation

  1. Split input into 2 regimes
  2. if (/.f64 (/.f64 (*.f64 (+.f64 alpha beta) (-.f64 beta alpha)) (+.f64 (+.f64 alpha beta) (*.f64 2 i))) (+.f64 (+.f64 (+.f64 alpha beta) (*.f64 2 i)) 2)) < -0.999998000000000054

    1. Initial program 62.3

      \[\frac{\frac{\frac{\left(\alpha + \beta\right) \cdot \left(\beta - \alpha\right)}{\left(\alpha + \beta\right) + 2 \cdot i}}{\left(\left(\alpha + \beta\right) + 2 \cdot i\right) + 2} + 1}{2} \]
    2. Taylor expanded in i around 0 61.8

      \[\leadsto \frac{\color{blue}{\left(-1 \cdot \frac{\left(2 \cdot \left(\beta + \alpha\right) + 2 \cdot \left(\beta + \left(2 + \alpha\right)\right)\right) \cdot \left(i \cdot \left(\beta - \alpha\right)\right)}{\left(\beta + \alpha\right) \cdot {\left(\beta + \left(2 + \alpha\right)\right)}^{2}} + \left(1 + \frac{\beta}{\beta + \left(2 + \alpha\right)}\right)\right) - \frac{\alpha}{\beta + \left(2 + \alpha\right)}}}{2} \]
    3. Simplified59.5

      \[\leadsto \frac{\color{blue}{\left(1 + \frac{\beta - \alpha}{\beta + \left(2 + \alpha\right)}\right) + \left(-\frac{\frac{2 \cdot \left(\left(\left(2 + \alpha\right) + \left(\beta + \left(\beta + \alpha\right)\right)\right) \cdot \left(i \cdot \left(\beta - \alpha\right)\right)\right)}{\beta + \alpha}}{{\left(\beta + \left(2 + \alpha\right)\right)}^{2}}\right)}}{2} \]
      Proof
      (/.f64 (+.f64 (+.f64 1 (/.f64 (-.f64 beta alpha) (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (/.f64 (*.f64 2 (*.f64 (+.f64 (+.f64 2 alpha) (+.f64 beta (+.f64 beta alpha))) (*.f64 i (-.f64 beta alpha)))) (+.f64 beta alpha)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 0 points increase in error, 0 points decrease in error
      (/.f64 (+.f64 (+.f64 1 (Rewrite=> div-sub_binary64 (-.f64 (/.f64 beta (+.f64 beta (+.f64 2 alpha))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))))) (neg.f64 (/.f64 (/.f64 (*.f64 2 (*.f64 (+.f64 (+.f64 2 alpha) (+.f64 beta (+.f64 beta alpha))) (*.f64 i (-.f64 beta alpha)))) (+.f64 beta alpha)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 0 points increase in error, 0 points decrease in error
      (/.f64 (+.f64 (Rewrite<= associate--l+_binary64 (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha))))) (neg.f64 (/.f64 (/.f64 (*.f64 2 (*.f64 (+.f64 (+.f64 2 alpha) (+.f64 beta (+.f64 beta alpha))) (*.f64 i (-.f64 beta alpha)))) (+.f64 beta alpha)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 0 points increase in error, 0 points decrease in error
      (/.f64 (+.f64 (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (/.f64 (*.f64 2 (*.f64 (+.f64 (+.f64 2 alpha) (+.f64 beta (Rewrite=> +-commutative_binary64 (+.f64 alpha beta)))) (*.f64 i (-.f64 beta alpha)))) (+.f64 beta alpha)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 0 points increase in error, 0 points decrease in error
      (/.f64 (+.f64 (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (/.f64 (*.f64 2 (*.f64 (Rewrite<= associate-+l+_binary64 (+.f64 (+.f64 (+.f64 2 alpha) beta) (+.f64 alpha beta))) (*.f64 i (-.f64 beta alpha)))) (+.f64 beta alpha)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 16 points increase in error, 0 points decrease in error
      (/.f64 (+.f64 (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (/.f64 (*.f64 2 (*.f64 (+.f64 (Rewrite<= +-commutative_binary64 (+.f64 beta (+.f64 2 alpha))) (+.f64 alpha beta)) (*.f64 i (-.f64 beta alpha)))) (+.f64 beta alpha)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 5 points increase in error, 11 points decrease in error
      (/.f64 (+.f64 (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (/.f64 (Rewrite<= associate-*l*_binary64 (*.f64 (*.f64 2 (+.f64 (+.f64 beta (+.f64 2 alpha)) (+.f64 alpha beta))) (*.f64 i (-.f64 beta alpha)))) (+.f64 beta alpha)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 0 points increase in error, 16 points decrease in error
      (/.f64 (+.f64 (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (/.f64 (*.f64 (*.f64 2 (Rewrite=> +-commutative_binary64 (+.f64 (+.f64 alpha beta) (+.f64 beta (+.f64 2 alpha))))) (*.f64 i (-.f64 beta alpha))) (+.f64 beta alpha)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 16 points increase in error, 0 points decrease in error
      (/.f64 (+.f64 (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (/.f64 (*.f64 (Rewrite<= distribute-lft-out_binary64 (+.f64 (*.f64 2 (+.f64 alpha beta)) (*.f64 2 (+.f64 beta (+.f64 2 alpha))))) (*.f64 i (-.f64 beta alpha))) (+.f64 beta alpha)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 0 points increase in error, 16 points decrease in error
      (/.f64 (+.f64 (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (/.f64 (*.f64 (+.f64 (*.f64 2 (Rewrite<= +-commutative_binary64 (+.f64 beta alpha))) (*.f64 2 (+.f64 beta (+.f64 2 alpha)))) (*.f64 i (-.f64 beta alpha))) (+.f64 beta alpha)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 16 points increase in error, 0 points decrease in error
      (/.f64 (+.f64 (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (/.f64 (*.f64 (+.f64 (*.f64 2 (+.f64 beta alpha)) (*.f64 2 (+.f64 beta (+.f64 2 alpha)))) (*.f64 i (-.f64 beta alpha))) (Rewrite=> +-commutative_binary64 (+.f64 alpha beta))) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 16 points increase in error, 0 points decrease in error
      (/.f64 (+.f64 (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (Rewrite<= associate-/r*_binary64 (/.f64 (*.f64 (+.f64 (*.f64 2 (+.f64 beta alpha)) (*.f64 2 (+.f64 beta (+.f64 2 alpha)))) (*.f64 i (-.f64 beta alpha))) (*.f64 (+.f64 alpha beta) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))))) 2): 16 points increase in error, 0 points decrease in error
      (/.f64 (+.f64 (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (*.f64 (+.f64 (*.f64 2 (+.f64 beta alpha)) (*.f64 2 (+.f64 beta (+.f64 2 alpha)))) (*.f64 i (-.f64 beta alpha))) (*.f64 (Rewrite<= +-commutative_binary64 (+.f64 beta alpha)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2))))) 2): 0 points increase in error, 16 points decrease in error
      (/.f64 (+.f64 (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))) (Rewrite<= mul-1-neg_binary64 (*.f64 -1 (/.f64 (*.f64 (+.f64 (*.f64 2 (+.f64 beta alpha)) (*.f64 2 (+.f64 beta (+.f64 2 alpha)))) (*.f64 i (-.f64 beta alpha))) (*.f64 (+.f64 beta alpha) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))))) 2): 16 points increase in error, 0 points decrease in error
      (/.f64 (Rewrite<= +-commutative_binary64 (+.f64 (*.f64 -1 (/.f64 (*.f64 (+.f64 (*.f64 2 (+.f64 beta alpha)) (*.f64 2 (+.f64 beta (+.f64 2 alpha)))) (*.f64 i (-.f64 beta alpha))) (*.f64 (+.f64 beta alpha) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) (-.f64 (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha)))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha)))))) 2): 16 points increase in error, 0 points decrease in error
      (/.f64 (Rewrite<= associate--l+_binary64 (-.f64 (+.f64 (*.f64 -1 (/.f64 (*.f64 (+.f64 (*.f64 2 (+.f64 beta alpha)) (*.f64 2 (+.f64 beta (+.f64 2 alpha)))) (*.f64 i (-.f64 beta alpha))) (*.f64 (+.f64 beta alpha) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) (+.f64 1 (/.f64 beta (+.f64 beta (+.f64 2 alpha))))) (/.f64 alpha (+.f64 beta (+.f64 2 alpha))))) 2): 0 points increase in error, 0 points decrease in error
    4. Taylor expanded in alpha around inf 57.2

      \[\leadsto \frac{\left(1 + \frac{\beta - \alpha}{\beta + \left(2 + \alpha\right)}\right) + \left(-\frac{\color{blue}{-4 \cdot \left(i \cdot \alpha\right)}}{{\left(\beta + \left(2 + \alpha\right)\right)}^{2}}\right)}{2} \]
    5. Simplified57.2

      \[\leadsto \frac{\left(1 + \frac{\beta - \alpha}{\beta + \left(2 + \alpha\right)}\right) + \left(-\frac{\color{blue}{i \cdot \left(\alpha \cdot -4\right)}}{{\left(\beta + \left(2 + \alpha\right)\right)}^{2}}\right)}{2} \]
      Proof
      (/.f64 (+.f64 (+.f64 1 (/.f64 (-.f64 beta alpha) (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (*.f64 i (*.f64 alpha -4)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 0 points increase in error, 0 points decrease in error
      (/.f64 (+.f64 (+.f64 1 (/.f64 (-.f64 beta alpha) (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (Rewrite<= associate-*l*_binary64 (*.f64 (*.f64 i alpha) -4)) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 0 points increase in error, 0 points decrease in error
      (/.f64 (+.f64 (+.f64 1 (/.f64 (-.f64 beta alpha) (+.f64 beta (+.f64 2 alpha)))) (neg.f64 (/.f64 (Rewrite<= *-commutative_binary64 (*.f64 -4 (*.f64 i alpha))) (pow.f64 (+.f64 beta (+.f64 2 alpha)) 2)))) 2): 0 points increase in error, 0 points decrease in error
    6. Taylor expanded in alpha around inf 5.9

      \[\leadsto \color{blue}{0.5 \cdot \frac{\left(2 + 2 \cdot \beta\right) - -4 \cdot i}{\alpha}} \]

    if -0.999998000000000054 < (/.f64 (/.f64 (*.f64 (+.f64 alpha beta) (-.f64 beta alpha)) (+.f64 (+.f64 alpha beta) (*.f64 2 i))) (+.f64 (+.f64 (+.f64 alpha beta) (*.f64 2 i)) 2))

    1. Initial program 12.7

      \[\frac{\frac{\frac{\left(\alpha + \beta\right) \cdot \left(\beta - \alpha\right)}{\left(\alpha + \beta\right) + 2 \cdot i}}{\left(\left(\alpha + \beta\right) + 2 \cdot i\right) + 2} + 1}{2} \]
    2. Simplified0.0

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{\alpha + \beta}{\beta + \mathsf{fma}\left(2, i, \alpha\right)}, \frac{\beta - \alpha}{\alpha + \left(\beta + \mathsf{fma}\left(2, i, 2\right)\right)}, 1\right)}{2}} \]
      Proof
      (/.f64 (fma.f64 (/.f64 (+.f64 alpha beta) (+.f64 beta (fma.f64 2 i alpha))) (/.f64 (-.f64 beta alpha) (+.f64 alpha (+.f64 beta (fma.f64 2 i 2)))) 1) 2): 0 points increase in error, 0 points decrease in error
      (/.f64 (fma.f64 (/.f64 (+.f64 alpha beta) (+.f64 beta (Rewrite<= fma-def_binary64 (+.f64 (*.f64 2 i) alpha)))) (/.f64 (-.f64 beta alpha) (+.f64 alpha (+.f64 beta (fma.f64 2 i 2)))) 1) 2): 0 points increase in error, 0 points decrease in error
      (/.f64 (fma.f64 (/.f64 (+.f64 alpha beta) (+.f64 beta (Rewrite<= +-commutative_binary64 (+.f64 alpha (*.f64 2 i))))) (/.f64 (-.f64 beta alpha) (+.f64 alpha (+.f64 beta (fma.f64 2 i 2)))) 1) 2): 2 points increase in error, 0 points decrease in error
      (/.f64 (fma.f64 (/.f64 (+.f64 alpha beta) (Rewrite<= associate-+l+_binary64 (+.f64 (+.f64 beta alpha) (*.f64 2 i)))) (/.f64 (-.f64 beta alpha) (+.f64 alpha (+.f64 beta (fma.f64 2 i 2)))) 1) 2): 0 points increase in error, 2 points decrease in error
      (/.f64 (fma.f64 (/.f64 (+.f64 alpha beta) (+.f64 (Rewrite<= +-commutative_binary64 (+.f64 alpha beta)) (*.f64 2 i))) (/.f64 (-.f64 beta alpha) (+.f64 alpha (+.f64 beta (fma.f64 2 i 2)))) 1) 2): 0 points increase in error, 0 points decrease in error
      (/.f64 (fma.f64 (/.f64 (+.f64 alpha beta) (+.f64 (+.f64 alpha beta) (*.f64 2 i))) (/.f64 (-.f64 beta alpha) (+.f64 alpha (+.f64 beta (Rewrite<= fma-def_binary64 (+.f64 (*.f64 2 i) 2))))) 1) 2): 11 points increase in error, 0 points decrease in error
      (/.f64 (fma.f64 (/.f64 (+.f64 alpha beta) (+.f64 (+.f64 alpha beta) (*.f64 2 i))) (/.f64 (-.f64 beta alpha) (Rewrite<= associate-+l+_binary64 (+.f64 (+.f64 alpha beta) (+.f64 (*.f64 2 i) 2)))) 1) 2): 0 points increase in error, 11 points decrease in error
      (/.f64 (fma.f64 (/.f64 (+.f64 alpha beta) (+.f64 (+.f64 alpha beta) (*.f64 2 i))) (/.f64 (-.f64 beta alpha) (Rewrite<= associate-+l+_binary64 (+.f64 (+.f64 (+.f64 alpha beta) (*.f64 2 i)) 2))) 1) 2): 11 points increase in error, 0 points decrease in error
      (/.f64 (Rewrite<= fma-def_binary64 (+.f64 (*.f64 (/.f64 (+.f64 alpha beta) (+.f64 (+.f64 alpha beta) (*.f64 2 i))) (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 (+.f64 alpha beta) (*.f64 2 i)) 2))) 1)) 2): 0 points increase in error, 11 points decrease in error
      (/.f64 (+.f64 (Rewrite<= times-frac_binary64 (/.f64 (*.f64 (+.f64 alpha beta) (-.f64 beta alpha)) (*.f64 (+.f64 (+.f64 alpha beta) (*.f64 2 i)) (+.f64 (+.f64 (+.f64 alpha beta) (*.f64 2 i)) 2)))) 1) 2): 0 points increase in error, 0 points decrease in error
      (/.f64 (+.f64 (Rewrite=> associate-/r*_binary64 (/.f64 (/.f64 (*.f64 (+.f64 alpha beta) (-.f64 beta alpha)) (+.f64 (+.f64 alpha beta) (*.f64 2 i))) (+.f64 (+.f64 (+.f64 alpha beta) (*.f64 2 i)) 2))) 1) 2): 0 points increase in error, 0 points decrease in error
  3. Recombined 2 regimes into one program.
  4. Final simplification1.4

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\frac{\left(\alpha + \beta\right) \cdot \left(\beta - \alpha\right)}{\left(\alpha + \beta\right) + 2 \cdot i}}{2 + \left(\left(\alpha + \beta\right) + 2 \cdot i\right)} \leq -0.999998:\\ \;\;\;\;0.5 \cdot \frac{\left(2 + \beta \cdot 2\right) + i \cdot 4}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\frac{\alpha + \beta}{\beta + \mathsf{fma}\left(2, i, \alpha\right)}, \frac{\beta - \alpha}{\alpha + \left(\beta + \mathsf{fma}\left(2, i, 2\right)\right)}, 1\right)}{2}\\ \end{array} \]

Alternatives

Alternative 1
Error1.4
Cost9796
\[\begin{array}{l} t_0 := \left(\alpha + \beta\right) + 2 \cdot i\\ t_1 := 2 + t_0\\ \mathbf{if}\;\frac{\frac{\left(\alpha + \beta\right) \cdot \left(\beta - \alpha\right)}{t_0}}{t_1} \leq -0.999998:\\ \;\;\;\;0.5 \cdot \frac{\left(2 + \beta \cdot 2\right) + i \cdot 4}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + \frac{\left(\beta - \alpha\right) \cdot \frac{\alpha + \beta}{\mathsf{fma}\left(2, i, \alpha + \beta\right)}}{t_1}}{2}\\ \end{array} \]
Alternative 2
Error2.3
Cost2500
\[\begin{array}{l} t_0 := \left(\alpha + \beta\right) + 2 \cdot i\\ \mathbf{if}\;\frac{\frac{\left(\alpha + \beta\right) \cdot \left(\beta - \alpha\right)}{t_0}}{2 + t_0} \leq -0.5:\\ \;\;\;\;0.5 \cdot \frac{\left(2 + \beta \cdot 2\right) + i \cdot 4}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + \frac{\beta}{\beta + \left(2 + 2 \cdot i\right)}}{2}\\ \end{array} \]
Alternative 3
Error12.1
Cost1228
\[\begin{array}{l} \mathbf{if}\;\alpha \leq 8.8 \cdot 10^{+24}:\\ \;\;\;\;\frac{1 + \frac{\beta}{\beta + 2}}{2}\\ \mathbf{elif}\;\alpha \leq 7.2 \cdot 10^{+49}:\\ \;\;\;\;\frac{\frac{2 + i \cdot 4}{\alpha}}{2}\\ \mathbf{elif}\;\alpha \leq 6 \cdot 10^{+188}:\\ \;\;\;\;\frac{1 + \frac{\beta}{\beta + \left(\alpha + 2\right)}}{2}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \frac{\left(2 + \beta \cdot 2\right) + i \cdot 4}{\alpha}\\ \end{array} \]
Alternative 4
Error13.8
Cost1101
\[\begin{array}{l} \mathbf{if}\;\alpha \leq 7.6 \cdot 10^{+24}:\\ \;\;\;\;\frac{1 + \frac{\beta}{\beta + 2}}{2}\\ \mathbf{elif}\;\alpha \leq 4.3 \cdot 10^{+49} \lor \neg \left(\alpha \leq 7 \cdot 10^{+188}\right):\\ \;\;\;\;\frac{\frac{2 + i \cdot 4}{\alpha}}{2}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + \frac{\beta}{\beta + \left(\alpha + 2\right)}}{2}\\ \end{array} \]
Alternative 5
Error13.8
Cost973
\[\begin{array}{l} \mathbf{if}\;\alpha \leq 8.8 \cdot 10^{+24}:\\ \;\;\;\;\frac{1 + \frac{\beta}{\beta + 2}}{2}\\ \mathbf{elif}\;\alpha \leq 1.65 \cdot 10^{+50} \lor \neg \left(\alpha \leq 5.4 \cdot 10^{+144}\right):\\ \;\;\;\;\frac{\frac{2 + i \cdot 4}{\alpha}}{2}\\ \mathbf{else}:\\ \;\;\;\;0.5\\ \end{array} \]
Alternative 6
Error15.0
Cost972
\[\begin{array}{l} t_0 := \frac{1 + \frac{\beta}{\beta + 2}}{2}\\ \mathbf{if}\;\alpha \leq 8.8 \cdot 10^{+24}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;\alpha \leq 2.1 \cdot 10^{+50}:\\ \;\;\;\;\frac{\frac{2}{\alpha}}{2}\\ \mathbf{elif}\;\alpha \leq 1.55 \cdot 10^{+189}:\\ \;\;\;\;t_0\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{2 + \beta \cdot 2}{\alpha}}{2}\\ \end{array} \]
Alternative 7
Error15.9
Cost708
\[\begin{array}{l} \mathbf{if}\;i \leq 10^{+92}:\\ \;\;\;\;\frac{1 + \frac{\beta}{\beta + 2}}{2}\\ \mathbf{else}:\\ \;\;\;\;0.5\\ \end{array} \]
Alternative 8
Error18.2
Cost196
\[\begin{array}{l} \mathbf{if}\;\beta \leq 1.12 \cdot 10^{+117}:\\ \;\;\;\;0.5\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]
Alternative 9
Error43.2
Cost64
\[1 \]

Error

Reproduce

herbie shell --seed 2022343 
(FPCore (alpha beta i)
  :name "Octave 3.8, jcobi/2"
  :precision binary64
  :pre (and (and (> alpha -1.0) (> beta -1.0)) (> i 0.0))
  (/ (+ (/ (/ (* (+ alpha beta) (- beta alpha)) (+ (+ alpha beta) (* 2.0 i))) (+ (+ (+ alpha beta) (* 2.0 i)) 2.0)) 1.0) 2.0))