Fix benchmark harness recording zero timings under pandas 3 - #541
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times["time"].iloc[i] = ... is a chained assignment. pandas 3 rejects it with ChainedAssignmentError and discards the value, so every timing and memory figure the harness produced was its initial value. Use .loc instead.
abelianbee
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Marc-Antoine Schmidt (MarcAntoineSchmidtQC),
Jan Tilly (jtilly) and
Martin Stancsics (stanmart)
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September 15, 2026 07:46
Martin Stancsics (stanmart)
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Sep 15, 2026
Martin Stancsics (stanmart)
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Thank you, tiny nit aside looks good.
| bench_memory=False, | ||
| ) | ||
| assert times["time"].notna().all() | ||
| assert (times["time"] > 0).all() |
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| assert (times["time"] > 0).all() | |
| assert times["memory"].notna().all() |
Nit: this is a slightly more direct test
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The benchmark harness writes results with
times["time"].iloc[i] = ..., which is a chained assignment. Under pandas 3 copy-on-write that is rejected withChainedAssignmentErrorand the value is dropped, so every timing and memory figure the harness produced was its initial value. Switched to.loc.The new test fails on
mainand passes with the fix.Checklist
CHANGELOG.rstentry