Counting unique values in a column in pandas dataframe like in Qlik?
Count distinct values, use nunique: df[‘hID’].nunique() 5 Count only non-null values, use count: df[‘hID’].count() 8 Count total values including null values, use the size attribute: df[‘hID’].size 8 Edit to add condition Use boolean indexing: df.loc[df[‘mID’]==’A’,’hID’].agg([‘nunique’,’count’,’size’]) OR using query: df.query(‘mID == “A”‘)[‘hID’].agg([‘nunique’,’count’,’size’]) Output: nunique 5 count 5 size 5 Name: hID, dtype: int64