如何基于另一个df布尔值修改df？

Question

I got 2 DataFrames. df1 (booleans) and df2 (integers). I can't figure out how to modify df2 based on df1.

Goal: To modify df2 and change values to 100 if False in df1. If True don't change.

df1
date         x     y      w      z 
2017-02-02  True  False  True   True
2017-02-03  False True   True   True


df2
date         x    y    w   z 
2017-02-02   1    2    3   4
2017-02-03   2    4    1   3

Expectation

df2
date         x    y    w   z 
2017-02-02   1   100   3   4
2017-02-03   100  4    1   3

Answer 1

这可以通过一个简单的条件语句来实现

df2[df1==False] = 100

Answer 2

where + iloc

You can use pd.DataFrame.where , ensuring you choose only relevant columns (ie ignoring the first columns). There's usually never a need to explicitly check == False or == True with Pandas.

df2.iloc[:, 1:] = df2.iloc[:, 1:].where(df1.iloc[:, 1:], 100)

print(df2)

         date    x    y  w  z
0  2017-02-02    1  100  3  4
1  2017-02-03  100    4  1  3