Check if dataframe column is Categorical

Question

I can\'t seem to get a simple dtype check working with Pandas\' improved Categoricals in v0.15+. Basically I just want something like is_categorical(column) -> True

Answer 1

In my pandas version (v1.0.3), a shorter version of joris' answer is available.

df = pd.DataFrame({'noncat': [1, 2, 3], 'categ': pd.Categorical(['A', 'B', 'C'])})

print(isinstance(df.noncat.dtype, pd.CategoricalDtype))  # False
print(isinstance(df.categ.dtype, pd.CategoricalDtype))   # True

print(pd.CategoricalDtype.is_dtype(df.noncat)) # False
print(pd.CategoricalDtype.is_dtype(df.categ))  # True