\frac{\frac{\left(i \cdot \left(\left(\alpha + \beta\right) + i\right)\right) \cdot \left(\beta \cdot \alpha + i \cdot \left(\left(\alpha + \beta\right) + i\right)\right)}{\left(\left(\alpha + \beta\right) + 2 \cdot i\right) \cdot \left(\left(\alpha + \beta\right) + 2 \cdot i\right)}}{\left(\left(\alpha + \beta\right) + 2 \cdot i\right) \cdot \left(\left(\alpha + \beta\right) + 2 \cdot i\right) - 1}\begin{array}{l}
\mathbf{if}\;\alpha \le 1.10176367394638824 \cdot 10^{101}:\\
\;\;\;\;\sqrt{\frac{\frac{i \cdot \frac{\left(\alpha + \beta\right) + i}{\mathsf{fma}\left(i, 2, \alpha + \beta\right)}}{{\left(\left(\alpha + \beta\right) + 2 \cdot i\right)}^{3} + \mathsf{fma}\left(i, 2, \alpha + \beta\right) \cdot \left(-1\right)}}{\frac{1}{\mathsf{fma}\left(\beta, \alpha, i \cdot \left(\left(\alpha + \beta\right) + i\right)\right)}}} \cdot \sqrt{\frac{\frac{i \cdot \frac{\left(\alpha + \beta\right) + i}{\mathsf{fma}\left(i, 2, \alpha + \beta\right)}}{{\left(\left(\alpha + \beta\right) + 2 \cdot i\right)}^{3} + \mathsf{fma}\left(i, 2, \alpha + \beta\right) \cdot \left(-1\right)}}{\frac{1}{\mathsf{fma}\left(\beta, \alpha, i \cdot \left(\left(\alpha + \beta\right) + i\right)\right)}}}\\
\mathbf{else}:\\
\;\;\;\;0\\
\end{array}double code(double alpha, double beta, double i) {
return ((((i * ((alpha + beta) + i)) * ((beta * alpha) + (i * ((alpha + beta) + i)))) / (((alpha + beta) + (2.0 * i)) * ((alpha + beta) + (2.0 * i)))) / ((((alpha + beta) + (2.0 * i)) * ((alpha + beta) + (2.0 * i))) - 1.0));
}
double code(double alpha, double beta, double i) {
double VAR;
if ((alpha <= 1.1017636739463882e+101)) {
VAR = (sqrt((((i * (((alpha + beta) + i) / fma(i, 2.0, (alpha + beta)))) / (pow(((alpha + beta) + (2.0 * i)), 3.0) + (fma(i, 2.0, (alpha + beta)) * -1.0))) / (1.0 / fma(beta, alpha, (i * ((alpha + beta) + i)))))) * sqrt((((i * (((alpha + beta) + i) / fma(i, 2.0, (alpha + beta)))) / (pow(((alpha + beta) + (2.0 * i)), 3.0) + (fma(i, 2.0, (alpha + beta)) * -1.0))) / (1.0 / fma(beta, alpha, (i * ((alpha + beta) + i)))))));
} else {
VAR = 0.0;
}
return VAR;
}



Bits error versus alpha



Bits error versus beta



Bits error versus i
Results
if alpha < 1.1017636739463882e+101Initial program 51.6
Simplified50.7
rmApplied div-inv50.7
Applied associate-/r*50.7
Simplified45.9
rmApplied add-sqr-sqrt45.9
if 1.1017636739463882e+101 < alpha Initial program 63.0
Simplified59.3
Taylor expanded around inf 52.1
Final simplification47.3
herbie shell --seed 2020103 +o rules:numerics
(FPCore (alpha beta i)
:name "Octave 3.8, jcobi/4"
:precision binary64
:pre (and (> alpha -1) (> beta -1) (> i 1))
(/ (/ (* (* i (+ (+ alpha beta) i)) (+ (* beta alpha) (* i (+ (+ alpha beta) i)))) (* (+ (+ alpha beta) (* 2 i)) (+ (+ alpha beta) (* 2 i)))) (- (* (+ (+ alpha beta) (* 2 i)) (+ (+ alpha beta) (* 2 i))) 1)))