有條件地在多列上設置值

Question

我有一組將組件反映到另一列的列。 當該列為負數時，我需要將其歸零。 我還需要將所有組件列清零。 我該怎么做呢？

filter_col = [col for col in t18_df if col.startswith('aum_')]
t18_df.loc[t18_df['AUM'] < 0] # these rows should have zeroed values only on filter_col

Answer 1

您可以將filter_col傳遞給loc ：

filter_col = [col for col in t18_df if col.startswith('aum_')]

# zero out filter_col
t18_df.loc[t18_df['AUM'] < 0, filter_col] = 0

# zero out AUM itself
t18_df.loc[t18_df['AUM'] < 0, 'AUM'] = 0
# also
# t18_df['AUM'] = t18_df['AUM'].clip(0)