Hoist the float conversion out of the inner loop. #10430
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serhiy-storchaka
approved these changes
Nov 9, 2018
Lib/random.py
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| return [population[_int(random() * n)] for i in range(k)] | ||
| cum_weights = list(_itertools.accumulate(weights)) | ||
| elif weights is not None: | ||
| raise TypeError('Cannot specify both weights and cumulative weights') | ||
| if len(cum_weights) != n: | ||
| raise ValueError('The number of weights does not match the population') | ||
| bisect = _bisect.bisect | ||
| total = cum_weights[-1] | ||
| total = cum_weights[-1] + 0.0 |
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Maybe repeat the comment? The code above can be changed independently, and the comment can be lost.
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No need to assign PRs to me. Just add me to the list of reviewers. |
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@rhettinger: Status check is done, and it's a success ✅ . |
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@rhettinger: Status check is done, and it's a success ✅ . |
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Currently, the n and total variables get converted to floats each time they are multiplied by random(). This minor tweak does the conversion just once and gets a small speedup (approx 3%).