Average Error: 13.6 → 8.5
Time: 1.2m
Precision: 64
Internal precision: 128
\[w0 \cdot \sqrt{1 - {\left(\frac{M \cdot D}{2 \cdot d}\right)}^2 \cdot \frac{h}{\ell}}\]
\[w0 \cdot \sqrt{1 - {\left(\left(\frac{\sqrt[3]{M \cdot D}}{\sqrt[3]{2 \cdot d}} \cdot \sqrt[3]{\frac{M \cdot D}{2 \cdot d} \cdot h}\right) \cdot \sqrt[3]{\frac{1}{\ell}}\right)}^3}\]

Error

Bits error versus w0

Bits error versus M

Bits error versus D

Bits error versus h

Bits error versus l

Bits error versus d

Derivation

  1. Initial program 13.6

    \[w0 \cdot \sqrt{1 - {\left(\frac{M \cdot D}{2 \cdot d}\right)}^2 \cdot \frac{h}{\ell}}\]
  2. Using strategy rm
  3. Applied div-inv 13.6

    \[\leadsto w0 \cdot \sqrt{1 - {\left(\frac{M \cdot D}{2 \cdot d}\right)}^2 \cdot \color{blue}{\left(h \cdot \frac{1}{\ell}\right)}}\]
  4. Applied associate-*r* 10.8

    \[\leadsto w0 \cdot \sqrt{1 - \color{blue}{\left({\left(\frac{M \cdot D}{2 \cdot d}\right)}^2 \cdot h\right) \cdot \frac{1}{\ell}}}\]
  5. Using strategy rm
  6. Applied square-mult 10.8

    \[\leadsto w0 \cdot \sqrt{1 - \left(\color{blue}{\left(\frac{M \cdot D}{2 \cdot d} \cdot \frac{M \cdot D}{2 \cdot d}\right)} \cdot h\right) \cdot \frac{1}{\ell}}\]
  7. Applied associate-*l* 9.2

    \[\leadsto w0 \cdot \sqrt{1 - \color{blue}{\left(\frac{M \cdot D}{2 \cdot d} \cdot \left(\frac{M \cdot D}{2 \cdot d} \cdot h\right)\right)} \cdot \frac{1}{\ell}}\]
  8. Using strategy rm
  9. Applied add-cube-cbrt 9.3

    \[\leadsto w0 \cdot \sqrt{1 - \left(\frac{M \cdot D}{2 \cdot d} \cdot \left(\frac{M \cdot D}{2 \cdot d} \cdot h\right)\right) \cdot \color{blue}{{\left(\sqrt[3]{\frac{1}{\ell}}\right)}^3}}\]
  10. Applied add-cube-cbrt 9.3

    \[\leadsto w0 \cdot \sqrt{1 - \left(\frac{M \cdot D}{2 \cdot d} \cdot \color{blue}{{\left(\sqrt[3]{\frac{M \cdot D}{2 \cdot d} \cdot h}\right)}^3}\right) \cdot {\left(\sqrt[3]{\frac{1}{\ell}}\right)}^3}\]
  11. Applied add-cube-cbrt 9.3

    \[\leadsto w0 \cdot \sqrt{1 - \left(\frac{M \cdot D}{\color{blue}{{\left(\sqrt[3]{2 \cdot d}\right)}^3}} \cdot {\left(\sqrt[3]{\frac{M \cdot D}{2 \cdot d} \cdot h}\right)}^3\right) \cdot {\left(\sqrt[3]{\frac{1}{\ell}}\right)}^3}\]
  12. Applied add-cube-cbrt 9.3

    \[\leadsto w0 \cdot \sqrt{1 - \left(\frac{\color{blue}{{\left(\sqrt[3]{M \cdot D}\right)}^3}}{{\left(\sqrt[3]{2 \cdot d}\right)}^3} \cdot {\left(\sqrt[3]{\frac{M \cdot D}{2 \cdot d} \cdot h}\right)}^3\right) \cdot {\left(\sqrt[3]{\frac{1}{\ell}}\right)}^3}\]
  13. Applied cube-undiv 9.3

    \[\leadsto w0 \cdot \sqrt{1 - \left(\color{blue}{{\left(\frac{\sqrt[3]{M \cdot D}}{\sqrt[3]{2 \cdot d}}\right)}^3} \cdot {\left(\sqrt[3]{\frac{M \cdot D}{2 \cdot d} \cdot h}\right)}^3\right) \cdot {\left(\sqrt[3]{\frac{1}{\ell}}\right)}^3}\]
  14. Applied cube-unprod 9.3

    \[\leadsto w0 \cdot \sqrt{1 - \color{blue}{{\left(\frac{\sqrt[3]{M \cdot D}}{\sqrt[3]{2 \cdot d}} \cdot \sqrt[3]{\frac{M \cdot D}{2 \cdot d} \cdot h}\right)}^3} \cdot {\left(\sqrt[3]{\frac{1}{\ell}}\right)}^3}\]
  15. Applied cube-unprod 8.5

    \[\leadsto w0 \cdot \sqrt{1 - \color{blue}{{\left(\left(\frac{\sqrt[3]{M \cdot D}}{\sqrt[3]{2 \cdot d}} \cdot \sqrt[3]{\frac{M \cdot D}{2 \cdot d} \cdot h}\right) \cdot \sqrt[3]{\frac{1}{\ell}}\right)}^3}}\]
  16. Removed slow pow expressions

Runtime

Time bar (total: 1.2m) Debug log

Please include this information when filing a bug report:

herbie --seed '#(3549487404 3716299900 735888072 2601173891 48456361 1960986808)'
(FPCore (w0 M D h l d)
  :name "Henrywood and Agarwal, Equation (9a)"
  (* w0 (sqrt (- 1 (* (sqr (/ (* M D) (* 2 d))) (/ h l))))))