anti-join-pandas

anti_join.py

import pandas as pd

def anti_join(x, y, on):
    """Return rows in x which are not present in y"""
    ans = pd.merge(left=x, right=y, how='left', indicator=True, on=on)
    ans = ans.loc[ans._merge == 'left_only', :].drop(columns='_merge')
    return ans


def anti_join_all_cols(x, y):
    """Return rows in x which are not present in y"""
    assert set(x.columns.values) == set(y.columns.values)
    return anti_join(x, y, x.columns.tolist())