Average Error: 10.3 → 2.9
Time: 3.5s
Precision: 64
\[\frac{x - y \cdot z}{t - a \cdot z}\]
\[\frac{x}{t - a \cdot z} - \frac{1}{\frac{\frac{t}{z} - a}{y}}\]
\frac{x - y \cdot z}{t - a \cdot z}
\frac{x}{t - a \cdot z} - \frac{1}{\frac{\frac{t}{z} - a}{y}}
double f(double x, double y, double z, double t, double a) {
        double r937763 = x;
        double r937764 = y;
        double r937765 = z;
        double r937766 = r937764 * r937765;
        double r937767 = r937763 - r937766;
        double r937768 = t;
        double r937769 = a;
        double r937770 = r937769 * r937765;
        double r937771 = r937768 - r937770;
        double r937772 = r937767 / r937771;
        return r937772;
}

double f(double x, double y, double z, double t, double a) {
        double r937773 = x;
        double r937774 = t;
        double r937775 = a;
        double r937776 = z;
        double r937777 = r937775 * r937776;
        double r937778 = r937774 - r937777;
        double r937779 = r937773 / r937778;
        double r937780 = 1.0;
        double r937781 = r937774 / r937776;
        double r937782 = r937781 - r937775;
        double r937783 = y;
        double r937784 = r937782 / r937783;
        double r937785 = r937780 / r937784;
        double r937786 = r937779 - r937785;
        return r937786;
}

Error

Bits error versus x

Bits error versus y

Bits error versus z

Bits error versus t

Bits error versus a

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original10.3
Target1.5
Herbie2.9
\[\begin{array}{l} \mathbf{if}\;z \lt -32113435955957344:\\ \;\;\;\;\frac{x}{t - a \cdot z} - \frac{y}{\frac{t}{z} - a}\\ \mathbf{elif}\;z \lt 3.51395223729782958 \cdot 10^{-86}:\\ \;\;\;\;\left(x - y \cdot z\right) \cdot \frac{1}{t - a \cdot z}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{t - a \cdot z} - \frac{y}{\frac{t}{z} - a}\\ \end{array}\]

Derivation

  1. Initial program 10.3

    \[\frac{x - y \cdot z}{t - a \cdot z}\]
  2. Using strategy rm
  3. Applied div-sub10.3

    \[\leadsto \color{blue}{\frac{x}{t - a \cdot z} - \frac{y \cdot z}{t - a \cdot z}}\]
  4. Using strategy rm
  5. Applied associate-/l*7.7

    \[\leadsto \frac{x}{t - a \cdot z} - \color{blue}{\frac{y}{\frac{t - a \cdot z}{z}}}\]
  6. Using strategy rm
  7. Applied div-sub7.7

    \[\leadsto \frac{x}{t - a \cdot z} - \frac{y}{\color{blue}{\frac{t}{z} - \frac{a \cdot z}{z}}}\]
  8. Simplified2.7

    \[\leadsto \frac{x}{t - a \cdot z} - \frac{y}{\frac{t}{z} - \color{blue}{a}}\]
  9. Using strategy rm
  10. Applied clear-num2.9

    \[\leadsto \frac{x}{t - a \cdot z} - \color{blue}{\frac{1}{\frac{\frac{t}{z} - a}{y}}}\]
  11. Final simplification2.9

    \[\leadsto \frac{x}{t - a \cdot z} - \frac{1}{\frac{\frac{t}{z} - a}{y}}\]

Reproduce

herbie shell --seed 2020057 
(FPCore (x y z t a)
  :name "Diagrams.Solve.Tridiagonal:solveTriDiagonal from diagrams-solve-0.1, A"
  :precision binary64

  :herbie-target
  (if (< z -32113435955957344) (- (/ x (- t (* a z))) (/ y (- (/ t z) a))) (if (< z 3.5139522372978296e-86) (* (- x (* y z)) (/ 1 (- t (* a z)))) (- (/ x (- t (* a z))) (/ y (- (/ t z) a)))))

  (/ (- x (* y z)) (- t (* a z))))