Another modification to constants comparison #67
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Yurlungur
approved these changes
May 9, 2025
| bool eps_equal(const Real &a, const Real &b) const { | ||
| const Real diff = std::abs(a - b); | ||
| const Real scale = 0.5 * (std::abs(a) + std::abs(b)); | ||
| return diff / (scale + 1e-100) <= EPS; |
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I'm a little surprised this is more robust.
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Maybe something to do with storing the result of the operations before the comparison to eps?
https://godbolt.org/z/vc848vMds
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Or doing 0 < EPS * 1e-27 is not well defined (in the sense the RHS is set to 0?)
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yeah I think not dividing is maybe technically better. But changing < to <= and storing the pieces could for sure matter.
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Debug build of artemis crashed in the constants comparison (of
hspecifically). Seemed like a stupid floating point problem that was solved by making the comparison<=instead of<. I also went ahead and split out the difference and scale into separate variables for possible future debugging.