I have dataframe with many lines and columns, looking like this :

I would like to keep only the values that are different from the previous index and replace the others by 0. On the example dataframe, it would be :

What is a solution that works for any number of row/columns ?

CodePudding user response：

So you'd like to keep the values where the difference to previous row is not equal to 0 (i.e., they're not the same), and put 0 to other places:

>>> df.where(df.diff().ne(0), other=0)
       col1  col2
index
1         0     1
2         5     0
3         0     4
4         0     0
5         3     0
6         2     0
7         0     1
8         0     2