python - Pandas analogue of SQL's "NOT IN" operator -


suprisingly, can't find analogue of sql's "not in" operator in pandas dataframes.

a = pd.dataframe({'a':[6,8,3,9,5],                        'b':['ii','i','i','iii','ii']})  b = pd.dataframe({'c':[1,2,3,4,5]})

i want rows a, a doesn't contain values b's c. like:

a = a[ a.a not in b.c]

i think close - need isin ~ negate boolean mask - instead list use series b.c:

print (~a.a.isin(b.c)) 0     true 1     true 2    false 3     true 4    false name: a, dtype: bool  = a[~a.a.isin(b.c)] print (a)       b 0  6   ii 1  8    3  9  iii

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