I have a pandas DataFrame and want to find select the column with the most unique values. I already filtered the unique values with nunique(). How can I now choose the column with the highest nunique()?
This is my code so far:
numeric_columns = df.select_dtypes(include = (int or float))
unique = []
for column in numeric_columns:
unique.append(numeric_columns[column].nunique())
I later need to filter all the columns of my dataframe depending on this column(most uniques)
CodePudding user response:
Use DataFrame.select_dtypes
with np.number
, then get DataFrame.nunique
with column by maximal value by Series.idxmax
:
df = pd.DataFrame({'a':[1,2,3,4],'b':[1,2,2,2], 'c':list('abcd')})
print (df)
a b c
0 1 1 a
1 2 2 b
2 3 2 c
3 4 2 d
numeric = df.select_dtypes(include = np.number)
nu = numeric.nunique().idxmax()
print (nu)
a