Average Error: 31.4 → 8.9
Time: 40.7s
Precision: 64
Ground Truth: 128
\[\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}\]
\[\begin{array}{l} \mathbf{if}\;im \le -2.809105747846623 \cdot 10^{+30}:\\ \;\;\;\;\frac{\log \left(-im\right)}{\log 10}\\ \mathbf{if}\;im \le -2.6177813920228387 \cdot 10^{-236}:\\ \;\;\;\;\sqrt[3]{{\left(\frac{\log \left(\sqrt{{re}^2 + im \cdot im}\right)}{\log 10}\right)}^3}\\ \mathbf{if}\;im \le 6.202292738103542 \cdot 10^{-168}:\\ \;\;\;\;\frac{\log \left(-re\right)}{\log 10}\\ \mathbf{if}\;im \le 1.5950010569398068 \cdot 10^{+130}:\\ \;\;\;\;\frac{1}{\sqrt[3]{{\left(\frac{\log 10}{\log \left(\sqrt{{re}^2 + im \cdot im}\right)}\right)}^3}}\\ \mathbf{else}:\\ \;\;\;\;\frac{\log im}{\log 10}\\ \end{array}\]

Error

Bits error versus re

Bits error versus im

Derivation

  1. Split input into 5 regimes.
  2. if im < -2.809105747846623e+30

    1. Initial program 44.3

      \[\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}\]
    2. Applied simplify 44.3

      \[\leadsto \color{blue}{\frac{\log \left(\sqrt{{im}^2 + re \cdot re}\right)}{\log 10}}\]
    3. Applied taylor 0.6

      \[\leadsto \frac{\log \left(-1 \cdot im\right)}{\log 10}\]
    4. Taylor expanded around -inf 0.6

      \[\leadsto \frac{\log \color{blue}{\left(-1 \cdot im\right)}}{\log 10}\]
    5. Applied simplify 0.6

      \[\leadsto \color{blue}{\frac{\log \left(-im\right)}{\log 10}}\]

    if -2.809105747846623e+30 < im < -2.6177813920228387e-236

    1. Initial program 19.3

      \[\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}\]
    2. Applied simplify 19.3

      \[\leadsto \color{blue}{\frac{\log \left(\sqrt{{im}^2 + re \cdot re}\right)}{\log 10}}\]
    3. Using strategy rm
    4. Applied add-cbrt-cube 19.9

      \[\leadsto \frac{\log \left(\sqrt{{im}^2 + re \cdot re}\right)}{\color{blue}{\sqrt[3]{{\left(\log 10\right)}^3}}}\]
    5. Applied add-cbrt-cube 19.8

      \[\leadsto \frac{\color{blue}{\sqrt[3]{{\left(\log \left(\sqrt{{im}^2 + re \cdot re}\right)\right)}^3}}}{\sqrt[3]{{\left(\log 10\right)}^3}}\]
    6. Applied cbrt-undiv 19.4

      \[\leadsto \color{blue}{\sqrt[3]{\frac{{\left(\log \left(\sqrt{{im}^2 + re \cdot re}\right)\right)}^3}{{\left(\log 10\right)}^3}}}\]
    7. Applied simplify 19.4

      \[\leadsto \sqrt[3]{\color{blue}{{\left(\frac{\log \left(\sqrt{{re}^2 + im \cdot im}\right)}{\log 10}\right)}^3}}\]

    if -2.6177813920228387e-236 < im < 6.202292738103542e-168

    1. Initial program 29.9

      \[\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}\]
    2. Applied simplify 29.9

      \[\leadsto \color{blue}{\frac{\log \left(\sqrt{{im}^2 + re \cdot re}\right)}{\log 10}}\]
    3. Using strategy rm
    4. Applied clear-num 29.9

      \[\leadsto \color{blue}{\frac{1}{\frac{\log 10}{\log \left(\sqrt{{im}^2 + re \cdot re}\right)}}}\]
    5. Using strategy rm
    6. Applied add-cbrt-cube 30.0

      \[\leadsto \frac{1}{\frac{\log 10}{\color{blue}{\sqrt[3]{{\left(\log \left(\sqrt{{im}^2 + re \cdot re}\right)\right)}^3}}}}\]
    7. Applied add-cbrt-cube 30.3

      \[\leadsto \frac{1}{\frac{\color{blue}{\sqrt[3]{{\left(\log 10\right)}^3}}}{\sqrt[3]{{\left(\log \left(\sqrt{{im}^2 + re \cdot re}\right)\right)}^3}}}\]
    8. Applied cbrt-undiv 30.0

      \[\leadsto \frac{1}{\color{blue}{\sqrt[3]{\frac{{\left(\log 10\right)}^3}{{\left(\log \left(\sqrt{{im}^2 + re \cdot re}\right)\right)}^3}}}}\]
    9. Applied simplify 30.0

      \[\leadsto \frac{1}{\sqrt[3]{\color{blue}{{\left(\frac{\log 10}{\log \left(\sqrt{{re}^2 + im \cdot im}\right)}\right)}^3}}}\]
    10. Applied taylor 0.7

      \[\leadsto \frac{1}{\sqrt[3]{{\left(\frac{\log 10}{\log \left(-1 \cdot re\right)}\right)}^3}}\]
    11. Taylor expanded around -inf 0.7

      \[\leadsto \frac{1}{\sqrt[3]{{\left(\frac{\log 10}{\log \color{blue}{\left(-1 \cdot re\right)}}\right)}^3}}\]
    12. Applied simplify 0.6

      \[\leadsto \color{blue}{\frac{\log \left(-re\right)}{\log 10}}\]

    if 6.202292738103542e-168 < im < 1.5950010569398068e+130

    1. Initial program 15.4

      \[\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}\]
    2. Applied simplify 15.4

      \[\leadsto \color{blue}{\frac{\log \left(\sqrt{{im}^2 + re \cdot re}\right)}{\log 10}}\]
    3. Using strategy rm
    4. Applied clear-num 15.4

      \[\leadsto \color{blue}{\frac{1}{\frac{\log 10}{\log \left(\sqrt{{im}^2 + re \cdot re}\right)}}}\]
    5. Using strategy rm
    6. Applied add-cbrt-cube 15.5

      \[\leadsto \frac{1}{\frac{\log 10}{\color{blue}{\sqrt[3]{{\left(\log \left(\sqrt{{im}^2 + re \cdot re}\right)\right)}^3}}}}\]
    7. Applied add-cbrt-cube 15.9

      \[\leadsto \frac{1}{\frac{\color{blue}{\sqrt[3]{{\left(\log 10\right)}^3}}}{\sqrt[3]{{\left(\log \left(\sqrt{{im}^2 + re \cdot re}\right)\right)}^3}}}\]
    8. Applied cbrt-undiv 15.4

      \[\leadsto \frac{1}{\color{blue}{\sqrt[3]{\frac{{\left(\log 10\right)}^3}{{\left(\log \left(\sqrt{{im}^2 + re \cdot re}\right)\right)}^3}}}}\]
    9. Applied simplify 15.5

      \[\leadsto \frac{1}{\sqrt[3]{\color{blue}{{\left(\frac{\log 10}{\log \left(\sqrt{{re}^2 + im \cdot im}\right)}\right)}^3}}}\]

    if 1.5950010569398068e+130 < im

    1. Initial program 56.2

      \[\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}\]
    2. Applied simplify 56.2

      \[\leadsto \color{blue}{\frac{\log \left(\sqrt{{im}^2 + re \cdot re}\right)}{\log 10}}\]
    3. Applied taylor 0.6

      \[\leadsto \frac{\log im}{\log 10}\]
    4. Taylor expanded around inf 0.6

      \[\leadsto \frac{\log \color{blue}{im}}{\log 10}\]
  3. Recombined 5 regimes into one program.
  4. Removed slow pow expressions

Runtime

Total time: 40.7s Debug log

Please include this information when filing a bug report:

herbie --seed '#(3642402179 2388761754 3684707313 2191577141 461247401 4148109162)'
(FPCore (re im)
  :name "math.log10 on complex, real part"
  (/ (log (sqrt (+ (* re re) (* im im)))) (log 10)))