math.sumprod() missing one case for combined int/float inputs.
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@rhettinger is already working on this.
Since Sep 17, 2025.
extension-modules
type-bug
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- Python
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Description
Bug report
Bug description:
The sumprod function has high precision paths for int/int, int/float, and float/float inputs. However it missed a case when an int/int pair follows another pair that contained a float. In other words, it assumes that once a float is encountered, that subsequent inputs won't contain a pair of ints.
>>> import math
>>> data = [-0.01, 1, -1, 0.01]
>>> math.sumprod(data, [1, 1, 1, 1])
-8.673617379884035e-18
>>> math.sumprod(data, [1.0, 1.0, 1.0, 1.0])
0.0
CPython versions tested on:
3.13, 3.15, 3.14
Operating systems tested on:
macOS
Linked PRs
- gh-139075
- gh-139085
- gh-139086
- gh-139092
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