Average Error: 29.6 → 16.8
Time: 2.6s
Precision: 64
Internal Precision: 128
\[\sqrt{re \cdot re + im \cdot im}\]
\[\begin{array}{l} \mathbf{if}\;re \le -4.010025314837191 \cdot 10^{+152}:\\ \;\;\;\;-re\\ \mathbf{elif}\;re \le -7.195014277572845 \cdot 10^{-271}:\\ \;\;\;\;\sqrt{im \cdot im + re \cdot re}\\ \mathbf{elif}\;re \le 4.170146857658731 \cdot 10^{-237}:\\ \;\;\;\;im\\ \mathbf{elif}\;re \le 4.769476277215655 \cdot 10^{+147}:\\ \;\;\;\;\sqrt{im \cdot im + re \cdot re}\\ \mathbf{else}:\\ \;\;\;\;re\\ \end{array}\]

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 < -4.010025314837191e+152

    1. Initial program 59.2

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

      \[\leadsto \sqrt{re \cdot re + im \cdot im}\]
    3. Taylor expanded around -inf 8.5

      \[\leadsto \color{blue}{-1 \cdot re}\]
    4. Simplified8.5

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

    if -4.010025314837191e+152 < re < -7.195014277572845e-271 or 4.170146857658731e-237 < re < 4.769476277215655e+147

    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 -7.195014277572845e-271 < re < 4.170146857658731e-237

    1. Initial program 29.6

      \[\sqrt{re \cdot re + im \cdot im}\]
    2. Initial simplification29.6

      \[\leadsto \sqrt{re \cdot re + im \cdot im}\]
    3. Taylor expanded around 0 31.2

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

    if 4.769476277215655e+147 < re

    1. Initial program 57.4

      \[\sqrt{re \cdot re + im \cdot im}\]
    2. Initial simplification57.4

      \[\leadsto \sqrt{re \cdot re + im \cdot im}\]
    3. Taylor expanded around inf 8.4

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

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \le -4.010025314837191 \cdot 10^{+152}:\\ \;\;\;\;-re\\ \mathbf{elif}\;re \le -7.195014277572845 \cdot 10^{-271}:\\ \;\;\;\;\sqrt{im \cdot im + re \cdot re}\\ \mathbf{elif}\;re \le 4.170146857658731 \cdot 10^{-237}:\\ \;\;\;\;im\\ \mathbf{elif}\;re \le 4.769476277215655 \cdot 10^{+147}:\\ \;\;\;\;\sqrt{im \cdot im + re \cdot re}\\ \mathbf{else}:\\ \;\;\;\;re\\ \end{array}\]

Runtime

Time bar (total: 2.6s)Debug logProfile

herbie shell --seed 2018278 
(FPCore (re im)
  :name "math.abs on complex"
  (sqrt (+ (* re re) (* im im))))