AttributeError: 'Categorical' object has no attribute 'cat'

Question

In python dataframe while getting category codes after assigning a column to variable(y=df.column) is giving attribute error.

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While same is working fine if we directoly pass df.column to Categorical function.

Please don't add your code as pictures. See creating good pandas examples and create a minimal reproducible example — G. Anderson
– G. Anderson, Commented Jun 21, 2019 at 18:13
Rolling back your edit because it completely muddles up your post. Please copy paste the exact code in your images into your question, or not at all. — cs95
– cs95, Commented Jun 21, 2019 at 18:40
pd.Categorical(df.c1) gives arrays.categorical.Categorical object while series.Series object — camel_case
– camel_case, Commented Jan 9, 2023 at 23:10

cs95 · Accepted Answer · 2019-06-21 18:13:59Z

The .cat attribute is a categorical accessor associated with categorical dtype Series:

s = pd.Series(['a', 'b', 'a']).astype('category') s 0 a 1 b 2 a dtype: category Categories (2, object): [a, b] s.cat.codes 0 0 1 1 2 0 dtype: int8

OTOH, pd.Category returns a pandas.core.arrays.categorical.Categorical object, which has these attributes defined on the object directly:

pd.Categorical(['a', 'b', 'c']) # [a, b, c] pd.Categorical(['a', 'b', 'c']) .codes # array([0, 1, 2], dtype=int8)

while printing 'y' and 'df.c1' both seems to be as categorical type
@VikashYadav Please carefully look at your code and images, they do not corroborate. Anyway, the whole point of my answer, is that df['c1'] is a Series, while pd.Categorical(...) (and anything you assign it to) is a Categorical object.

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