gh-140443: Use fma in loghelper to improve accuracy of log for very large integers
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…ery large integers
Replaced the expression computing the final result in loghelper with an
fma() call:
result = fma(func(2.0), (double)e, func(x));
This change reduces rounding error and improves the ULP distribution of
math.log10() for very large integer inputs.
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It's been a joy! Thank you for your efforts and patience. It's amazing how much "busy work" there is to make a 1-line change 🤣, eh?
It all looks good to me. I'll merge it tomorrow. Perhaps @StanFromIreland knows more than me about what kind of markup decorations are wanted in NEWS entries. I can never remember that stuff
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Thank you, @tim-one and @StanFromIreland, for your guidance throughout this PR (and thank you for pointing out my mistakes.) I’ve learned a great deal from your feedback and reviews. |
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…e-140443.wT5i1A.rst Co-authored-by: Stan Ulbrych <[email protected]>
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Replaced the expression computing the final result in loghelper with an fma() call:
This change reduces rounding error and improves the ULP distribution of math.log for very large integer inputs.