Python pandas apply function if a column value is not NULL
The problem is that pd.notnull([‘foo’, ‘bar’]) operates elementwise and returns array([ True, True], dtype=bool). Your if condition trys to convert that to a boolean, and that’s when you get the exception. To fix it, you could simply wrap the isnull statement with np.all: df[[‘A’,’C’]].apply(lambda x: my_func(x) if(np.all(pd.notnull(x[1]))) else x, axis = 1) Now you’ll see … Read more