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Behavior of Series.values when dtype is "category" is surprising

See original GitHub issue

Say I make a category-type Series:

s = pd.Series(["a", "b", "c"], dtype="category")

I want to pass this to a function that expects a numpy array, so I use the values property. According to the documentation:

s.values?

Type:        property
String form: <property object at 0x106d84050>
Docstring:
Return Series as ndarray

Returns
-------
arr : numpy.ndarray

However:

s.values

[a, b, c]
Categories (3, object): [a < b < c]

Issue Analytics

State:
Created 9 years ago
Comments:10 (10 by maintainers)

Top GitHub Comments

1reaction

jorisvandenbosschecommented, Feb 17, 2017

The docstring of .values is updated in the meantime (https://github.com/pandas-dev/pandas/pull/10477/files#diff-150fd3c5a732ae915ec47bc54a933c41R328), so closing this. The different output type is of course still confusing, but that is not something we are going to solve before pandas 2.

0reactions

jrebackcommented, Mar 3, 2015

i’ll clarify

I meant unadvertised. Its in the public-api.

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