Average Error: 29.5 → 16.8
Time: 3.9s
Precision: 64
Internal Precision: 128
\[\sqrt{re \cdot re + im \cdot im}\]
\[\begin{array}{l} \mathbf{if}\;re \le -5.313865136797356 \cdot 10^{+146}:\\ \;\;\;\;-re\\ \mathbf{elif}\;re \le 2.273780908986114 \cdot 10^{-292}:\\ \;\;\;\;\sqrt{im \cdot im + re \cdot re}\\ \mathbf{elif}\;re \le 1.4029821953931988 \cdot 10^{-209}:\\ \;\;\;\;im\\ \mathbf{elif}\;re \le 1.317497755195432 \cdot 10^{+154}:\\ \;\;\;\;\sqrt{im \cdot im + re \cdot re}\\ \mathbf{else}:\\ \;\;\;\;re\\ \end{array}\]

Error

Bits error versus re

Bits error versus im

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Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Split input into 4 regimes
  2. if re < -5.313865136797356e+146

    1. Initial program 57.0

      \[\sqrt{re \cdot re + im \cdot im}\]
    2. Initial simplification57.0

      \[\leadsto \sqrt{re \cdot re + im \cdot im}\]
    3. Taylor expanded around -inf 8.2

      \[\leadsto \color{blue}{-1 \cdot re}\]
    4. Simplified8.2

      \[\leadsto \color{blue}{-re}\]

    if -5.313865136797356e+146 < re < 2.273780908986114e-292 or 1.4029821953931988e-209 < re < 1.317497755195432e+154

    1. Initial program 18.3

      \[\sqrt{re \cdot re + im \cdot im}\]
    2. Initial simplification18.3

      \[\leadsto \sqrt{re \cdot re + im \cdot im}\]

    if 2.273780908986114e-292 < re < 1.4029821953931988e-209

    1. Initial program 29.9

      \[\sqrt{re \cdot re + im \cdot im}\]
    2. Initial simplification29.9

      \[\leadsto \sqrt{re \cdot re + im \cdot im}\]
    3. Taylor expanded around 0 36.4

      \[\leadsto \color{blue}{im}\]

    if 1.317497755195432e+154 < re

    1. Initial program 59.4

      \[\sqrt{re \cdot re + im \cdot im}\]
    2. Initial simplification59.4

      \[\leadsto \sqrt{re \cdot re + im \cdot im}\]
    3. Taylor expanded around inf 7.4

      \[\leadsto \color{blue}{re}\]
  3. Recombined 4 regimes into one program.
  4. Final simplification16.8

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \le -5.313865136797356 \cdot 10^{+146}:\\ \;\;\;\;-re\\ \mathbf{elif}\;re \le 2.273780908986114 \cdot 10^{-292}:\\ \;\;\;\;\sqrt{im \cdot im + re \cdot re}\\ \mathbf{elif}\;re \le 1.4029821953931988 \cdot 10^{-209}:\\ \;\;\;\;im\\ \mathbf{elif}\;re \le 1.317497755195432 \cdot 10^{+154}:\\ \;\;\;\;\sqrt{im \cdot im + re \cdot re}\\ \mathbf{else}:\\ \;\;\;\;re\\ \end{array}\]

Runtime

Time bar (total: 3.9s)Debug logProfile

herbie shell --seed 2018349 
(FPCore (re im)
  :name "math.abs on complex"
  (sqrt (+ (* re re) (* im im))))