Average Error: 29.5 → 16.7
Time: 3.3s
Precision: 64
Internal Precision: 320
\[\sqrt{re \cdot re + im \cdot im}\]
\[\begin{array}{l} \mathbf{if}\;re \le -6.98919469234238 \cdot 10^{+142}:\\ \;\;\;\;-re\\ \mathbf{elif}\;re \le 1.1329987674401443 \cdot 10^{+143}:\\ \;\;\;\;\sqrt{im \cdot im + re \cdot re}\\ \mathbf{else}:\\ \;\;\;\;re\\ \end{array}\]

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 3 regimes
  2. if re < -6.98919469234238e+142

    1. Initial program 55.9

      \[\sqrt{re \cdot re + im \cdot im}\]
    2. Initial simplification55.9

      \[\leadsto \sqrt{re \cdot re + im \cdot im}\]
    3. Taylor expanded around -inf 8.1

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

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

    if -6.98919469234238e+142 < re < 1.1329987674401443e+143

    1. Initial program 19.8

      \[\sqrt{re \cdot re + im \cdot im}\]
    2. Initial simplification19.8

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

    if 1.1329987674401443e+143 < re

    1. Initial program 55.6

      \[\sqrt{re \cdot re + im \cdot im}\]
    2. Initial simplification55.6

      \[\leadsto \sqrt{re \cdot re + im \cdot im}\]
    3. Taylor expanded around inf 8.8

      \[\leadsto \color{blue}{re}\]
  3. Recombined 3 regimes into one program.
  4. Final simplification16.7

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \le -6.98919469234238 \cdot 10^{+142}:\\ \;\;\;\;-re\\ \mathbf{elif}\;re \le 1.1329987674401443 \cdot 10^{+143}:\\ \;\;\;\;\sqrt{im \cdot im + re \cdot re}\\ \mathbf{else}:\\ \;\;\;\;re\\ \end{array}\]

Runtime

Time bar (total: 3.3s)Debug logProfile

herbie shell --seed 2018242 
(FPCore (re im)
  :name "math.abs on complex"
  (sqrt (+ (* re re) (* im im))))