pythonpandasboolean-logiclogical-operatorsboolean-operations

Element-wise logical OR in Pandas


I am aware that AND corresponds to & and NOT, ~. What is the element-wise logical OR operator? I know "or" itself is not what I am looking for.


Solution

  • The corresponding operator is |:

     df[(df < 3) | (df == 5)]
    

    would elementwise check if value is less than 3 or equal to 5.


    If you need a function to do this, we have np.logical_or. For two conditions, you can use

    df[np.logical_or(df<3, df==5)]
    

    Or, for multiple conditions use the logical_or.reduce,

    df[np.logical_or.reduce([df<3, df==5])]
    

    Since the conditions are specified as individual arguments, parentheses grouping is not needed.

    More information on logical operations with pandas can be found here.