Average Error: 14.1 → 0.2
Time: 22.4s
Precision: 64
\[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\]
↓
\[\frac{\frac{\left(\frac{\pi}{2} \cdot 1\right) \cdot \frac{\left(b - a\right) \cdot 1}{b + a}}{a \cdot b}}{b - a}\]
\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)
↓
\frac{\frac{\left(\frac{\pi}{2} \cdot 1\right) \cdot \frac{\left(b - a\right) \cdot 1}{b + a}}{a \cdot b}}{b - a}
double f(double a, double b) {
        double r78563 = atan2(1.0, 0.0);
        double r78564 = 2.0;
        double r78565 = r78563 / r78564;
        double r78566 = 1.0;
        double r78567 = b;
        double r78568 = r78567 * r78567;
        double r78569 = a;
        double r78570 = r78569 * r78569;
        double r78571 = r78568 - r78570;
        double r78572 = r78566 / r78571;
        double r78573 = r78565 * r78572;
        double r78574 = r78566 / r78569;
        double r78575 = r78566 / r78567;
        double r78576 = r78574 - r78575;
        double r78577 = r78573 * r78576;
        return r78577;
}
↓
double f(double a, double b) {
        double r78578 = atan2(1.0, 0.0);
        double r78579 = 2.0;
        double r78580 = r78578 / r78579;
        double r78581 = 1.0;
        double r78582 = r78580 * r78581;
        double r78583 = b;
        double r78584 = a;
        double r78585 = r78583 - r78584;
        double r78586 = r78585 * r78581;
        double r78587 = r78583 + r78584;
        double r78588 = r78586 / r78587;
        double r78589 = r78582 * r78588;
        double r78590 = r78584 * r78583;
        double r78591 = r78589 / r78590;
        double r78592 = r78591 / r78585;
        return r78592;
}

Error

Bits error versus a

Bits error versus b

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Initial program 14.1

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\]
  2. Using strategy rm

  3. Applied difference-of-squares9.2

    \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\]

  4. Applied *-un-lft-identity9.2

    \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\color{blue}{1 \cdot 1}}{\left(b + a\right) \cdot \left(b - a\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\]

  5. Applied times-frac8.7

    \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left(\frac{1}{b + a} \cdot \frac{1}{b - a}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\]

  6. Applied associate-*r*8.7

    \[\leadsto \color{blue}{\left(\left(\frac{\pi}{2} \cdot \frac{1}{b + a}\right) \cdot \frac{1}{b - a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\]

  7. Simplified8.7

    \[\leadsto \left(\color{blue}{\frac{\frac{\pi}{2}}{b + a}} \cdot \frac{1}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\]
  8. Using strategy rm

  9. Applied associate-*r/8.6

    \[\leadsto \color{blue}{\frac{\frac{\frac{\pi}{2}}{b + a} \cdot 1}{b - a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\]

  10. Applied associate-*l/0.3

    \[\leadsto \color{blue}{\frac{\left(\frac{\frac{\pi}{2}}{b + a} \cdot 1\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{b - a}}\]
  11. Using strategy rm

  12. Applied frac-sub0.3

    \[\leadsto \frac{\left(\frac{\frac{\pi}{2}}{b + a} \cdot 1\right) \cdot \color{blue}{\frac{1 \cdot b - a \cdot 1}{a \cdot b}}}{b - a}\]

  13. Applied associate-*r/0.3

    \[\leadsto \frac{\color{blue}{\frac{\left(\frac{\frac{\pi}{2}}{b + a} \cdot 1\right) \cdot \left(1 \cdot b - a \cdot 1\right)}{a \cdot b}}}{b - a}\]

  14. Simplified0.3

    \[\leadsto \frac{\frac{\color{blue}{\frac{\frac{\pi}{2} \cdot 1}{b + a} \cdot \left(1 \cdot \left(b - a\right)\right)}}{a \cdot b}}{b - a}\]
  15. Using strategy rm

  16. Applied div-inv0.3

    \[\leadsto \frac{\frac{\color{blue}{\left(\left(\frac{\pi}{2} \cdot 1\right) \cdot \frac{1}{b + a}\right)} \cdot \left(1 \cdot \left(b - a\right)\right)}{a \cdot b}}{b - a}\]

  17. Applied associate-*l*0.3

    \[\leadsto \frac{\frac{\color{blue}{\left(\frac{\pi}{2} \cdot 1\right) \cdot \left(\frac{1}{b + a} \cdot \left(1 \cdot \left(b - a\right)\right)\right)}}{a \cdot b}}{b - a}\]

  18. Simplified0.2

    \[\leadsto \frac{\frac{\left(\frac{\pi}{2} \cdot 1\right) \cdot \color{blue}{\frac{\left(b - a\right) \cdot 1}{b + a}}}{a \cdot b}}{b - a}\]

  19. Final simplification0.2

    \[\leadsto \frac{\frac{\left(\frac{\pi}{2} \cdot 1\right) \cdot \frac{\left(b - a\right) \cdot 1}{b + a}}{a \cdot b}}{b - a}\]

Reproduce

herbie shell --seed 2019303 +o rules:numerics
(FPCore (a b)
  :name "NMSE Section 6.1 mentioned, B"
  :precision binary64
  (* (* (/ PI 2) (/ 1 (- (* b b) (* a a)))) (- (/ 1 a) (/ 1 b))))