REF: consolidate casting in groupby agg_series

[jbrockmendel]

• closes #xxxx
• tests added / passed
• Ensure all linting tests pass, see here for how to run them
• whatsnew entry

[jbrockmendel]

These tests are for the low-level cython func, and this PR makes the casting from object take place after the cython call instead of within it. Nothing user facing.

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On Mon, May 3, 2021 at 8:17 AM Jeff Reback ***@***.***> wrote: ***@***.**** requested changes on this pull request. ------------------------------ In pandas/tests/groupby/test_bin_groupby.py <#41273 (comment)>: > @@ -20,7 +20,7 @@ def test_series_grouper(): grouper = libreduction.SeriesGrouper(obj, np.mean, labels, 2) result, counts = grouper.get_result() - expected = np.array([obj[3:6].mean(), obj[6:].mean()]) + expected = np.array([obj[3:6].mean(), obj[6:].mean()], dtype=object) these look like internal tests, but is anything user facing changed? (no looks like)? why are these now returning object? (e.g. can you just remove the cast_back above)? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#41273 (review)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AB5UM6EBWNTRNKVI3MBDDBLTL25AHANCNFSM437ZXAQA> .