Fix sort_values when column is all empty strings
#12988
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| if last := divisions[col].iloc[-1]: | ||
| divisions[col].iloc[-1] = chr(ord(last[0]) + 1) | ||
| else: | ||
| divisions[col].iloc[-1] = chr(1) # b/c "" < chr(1) |
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Interestingly, using chr(0) here doesn't work, because drop_duplicates below drops it by treating "" and chr(0) the same, even though "" < chr(0). Do we care that chr(1) is not printable?
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This is actually a bug in [i]loc.__setitem__:
import cudf
x = cudf.Series(["", chr(0)])
x.drop_duplicates() == x # True
y = cudf.Series(["a", "b"])
y.iloc[0] = ""
y.iloc[1] = chr(0)
y.iloc[0] == y.iloc[1] # True
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I guess in the case that last is the empty string, it suffices to provide any non-empty string as the upper bound on division?
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it suffices to provide any non-empty string
Yup. How about "wence was here"?
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"nonempty"? I don't like to leave footprints :).
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"this string intentionally left empty"
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I like David's suggestion (or we can wait for #12991 and use chr(0))
wence-
added
non-breaking
|
/merge |
Description
See test for simple MRE.
This fixes rapidsai/cugraph#3058
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