Fix decimal log precision for non-power values#20433
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kumarUjjawal wants to merge 3 commits intoapache:mainfrom
Open
Fix decimal log precision for non-power values#20433kumarUjjawal wants to merge 3 commits intoapache:mainfrom
kumarUjjawal wants to merge 3 commits intoapache:mainfrom
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@Jefffrey when you do get the time, can you take a look. |
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@martin-g if I could borrow your time here. |
martin-g
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Mar 9, 2026
Jefffrey
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Mar 12, 2026
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| if scale == 0 | ||
| && is_valid_integer_base(base) | ||
| && let Ok(unscaled) = u32::try_from(value) | ||
| && unscaled > 0 |
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I feel we'll need to reconsider this integer log path now that it's reduced to needing all these requirements:
- 0 scale
- integer base
- can unscale
Just for a more accurate computation 🤔
cc @theirix
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That's true. I would start with more test cases to express our expectations on int/float semantics, like stated in the PR description.
For unscaling, I believe it could be improved in general, there are some edge cases. One attempt is here #19874
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Which issue does this PR close?
Rationale for this change
The decimal log implementation used the integer ilog path whenever the base was an integer, which floors results for non‑power values. That produced incorrect outputs such as log(2, 10^35) returning 116 instead of 116.267...
What changes are included in this PR?
Are these changes tested?
Yes
Are there any user-facing changes?
No