\[\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}\]
Test:
math.log10 on complex, real part
Bits:
128 bits
Bits error versus re
Bits error versus im
Time: 9.1 s
Input Error: 14.8
Output Error: 6.8
Log:
Profile: 🕒
\(\begin{cases} \frac{3}{\log 10} \cdot \log \left(\sqrt[3]{-re}\right) & \text{when } re \le -7.494067f+15 \\ \frac{3}{1} \cdot \left(\frac{\frac{1}{3}}{1} \cdot \frac{\log \left(\sqrt{{re}^2 + im \cdot im}\right)}{\log 10}\right) & \text{when } re \le 3.2777988f+12 \\ \frac{\log re}{\log 10} & \text{otherwise} \end{cases}\)

    if re < -7.494067f+15

    1. Started with
      \[\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}\]
      26.9
    2. Applied simplify to get
      \[\color{red}{\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}} \leadsto \color{blue}{\frac{\log \left(\sqrt{{re}^2 + im \cdot im}\right)}{\log 10}}\]
      26.9
    3. Using strategy rm
      26.9
    4. Applied add-cube-cbrt to get
      \[\frac{\log \color{red}{\left(\sqrt{{re}^2 + im \cdot im}\right)}}{\log 10} \leadsto \frac{\log \color{blue}{\left({\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}^3\right)}}{\log 10}\]
      26.9
    5. Using strategy rm
      26.9
    6. Applied *-un-lft-identity to get
      \[\frac{\log \left({\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}^3\right)}{\color{red}{\log 10}} \leadsto \frac{\log \left({\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}^3\right)}{\color{blue}{1 \cdot \log 10}}\]
      26.9
    7. Applied pow3 to get
      \[\frac{\log \color{red}{\left({\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}^3\right)}}{1 \cdot \log 10} \leadsto \frac{\log \color{blue}{\left({\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}^{3}\right)}}{1 \cdot \log 10}\]
      26.9
    8. Applied log-pow to get
      \[\frac{\color{red}{\log \left({\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}^{3}\right)}}{1 \cdot \log 10} \leadsto \frac{\color{blue}{3 \cdot \log \left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}}{1 \cdot \log 10}\]
      26.9
    9. Applied times-frac to get
      \[\color{red}{\frac{3 \cdot \log \left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}{1 \cdot \log 10}} \leadsto \color{blue}{\frac{3}{1} \cdot \frac{\log \left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}{\log 10}}\]
      26.9
    10. Applied taylor to get
      \[\frac{3}{1} \cdot \frac{\log \left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}{\log 10} \leadsto \frac{3}{1} \cdot \frac{\log \left(\sqrt[3]{-1 \cdot re}\right)}{\log 10}\]
      0.2
    11. Taylor expanded around -inf to get
      \[\frac{3}{1} \cdot \frac{\log \left(\sqrt[3]{\color{red}{-1 \cdot re}}\right)}{\log 10} \leadsto \frac{3}{1} \cdot \frac{\log \left(\sqrt[3]{\color{blue}{-1 \cdot re}}\right)}{\log 10}\]
      0.2
    12. Applied simplify to get
      \[\color{red}{\frac{3}{1} \cdot \frac{\log \left(\sqrt[3]{-1 \cdot re}\right)}{\log 10}} \leadsto \color{blue}{\frac{3}{\log 10} \cdot \log \left(\sqrt[3]{-re}\right)}\]
      0.2

    if -7.494067f+15 < re < 3.2777988f+12

    1. Started with
      \[\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}\]
      9.8
    2. Applied simplify to get
      \[\color{red}{\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}} \leadsto \color{blue}{\frac{\log \left(\sqrt{{re}^2 + im \cdot im}\right)}{\log 10}}\]
      9.8
    3. Using strategy rm
      9.8
    4. Applied add-cube-cbrt to get
      \[\frac{\log \color{red}{\left(\sqrt{{re}^2 + im \cdot im}\right)}}{\log 10} \leadsto \frac{\log \color{blue}{\left({\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}^3\right)}}{\log 10}\]
      9.9
    5. Using strategy rm
      9.9
    6. Applied *-un-lft-identity to get
      \[\frac{\log \left({\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}^3\right)}{\color{red}{\log 10}} \leadsto \frac{\log \left({\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}^3\right)}{\color{blue}{1 \cdot \log 10}}\]
      9.9
    7. Applied pow3 to get
      \[\frac{\log \color{red}{\left({\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}^3\right)}}{1 \cdot \log 10} \leadsto \frac{\log \color{blue}{\left({\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}^{3}\right)}}{1 \cdot \log 10}\]
      9.9
    8. Applied log-pow to get
      \[\frac{\color{red}{\log \left({\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}^{3}\right)}}{1 \cdot \log 10} \leadsto \frac{\color{blue}{3 \cdot \log \left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}}{1 \cdot \log 10}\]
      9.9
    9. Applied times-frac to get
      \[\color{red}{\frac{3 \cdot \log \left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}{1 \cdot \log 10}} \leadsto \color{blue}{\frac{3}{1} \cdot \frac{\log \left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}{\log 10}}\]
      9.9
    10. Using strategy rm
      9.9
    11. Applied *-un-lft-identity to get
      \[\frac{3}{1} \cdot \frac{\log \left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}{\color{red}{\log 10}} \leadsto \frac{3}{1} \cdot \frac{\log \left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}{\color{blue}{1 \cdot \log 10}}\]
      9.9
    12. Applied pow1/3 to get
      \[\frac{3}{1} \cdot \frac{\log \color{red}{\left(\sqrt[3]{\sqrt{{re}^2 + im \cdot im}}\right)}}{1 \cdot \log 10} \leadsto \frac{3}{1} \cdot \frac{\log \color{blue}{\left({\left(\sqrt{{re}^2 + im \cdot im}\right)}^{\frac{1}{3}}\right)}}{1 \cdot \log 10}\]
      9.9
    13. Applied log-pow to get
      \[\frac{3}{1} \cdot \frac{\color{red}{\log \left({\left(\sqrt{{re}^2 + im \cdot im}\right)}^{\frac{1}{3}}\right)}}{1 \cdot \log 10} \leadsto \frac{3}{1} \cdot \frac{\color{blue}{\frac{1}{3} \cdot \log \left(\sqrt{{re}^2 + im \cdot im}\right)}}{1 \cdot \log 10}\]
      9.8
    14. Applied times-frac to get
      \[\frac{3}{1} \cdot \color{red}{\frac{\frac{1}{3} \cdot \log \left(\sqrt{{re}^2 + im \cdot im}\right)}{1 \cdot \log 10}} \leadsto \frac{3}{1} \cdot \color{blue}{\left(\frac{\frac{1}{3}}{1} \cdot \frac{\log \left(\sqrt{{re}^2 + im \cdot im}\right)}{\log 10}\right)}\]
      9.8

    if 3.2777988f+12 < re

    1. Started with
      \[\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}\]
      24.8
    2. Applied simplify to get
      \[\color{red}{\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}} \leadsto \color{blue}{\frac{\log \left(\sqrt{{re}^2 + im \cdot im}\right)}{\log 10}}\]
      24.8
    3. Applied taylor to get
      \[\frac{\log \left(\sqrt{{re}^2 + im \cdot im}\right)}{\log 10} \leadsto \frac{\log re}{\log 10}\]
      0.3
    4. Taylor expanded around inf to get
      \[\frac{\log \color{red}{re}}{\log 10} \leadsto \frac{\log \color{blue}{re}}{\log 10}\]
      0.3

  1. Removed slow pow expressions

Original test:


(lambda ((re default) (im default))
  #:name "math.log10 on complex, real part"
  (/ (log (sqrt (+ (* re re) (* im im)))) (log 10)))