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I have a huge dataframe with 40 columns (10 groups of 4 columns), with value in some groups and NaN for others. I want the values for all the row left-shifted, such that wherever values be present in that row, the final Dataframe should be filled with Group1 -> Group 2 -> Group 3 and so on.

Here is a sample dataframe and the required output below:

Dataframe df1

Here is the required output:

Dataframe df2

I have used the below code to achieve shifting the values left. However, if a value is missing in an available group, e.g. Item 2 type-1, or Item 3 cat-2, the below code will ignore that and will replace it with the value to its right, and so on.

v = df1.values
a = [[n]*v.shape[1] for n in range(v.shape[0])]
b = pd.isnull(v).argsort(axis=1, kind = 'mergesort')
df2 = pd.DataFrame(v[a,b],df1.index,df1.columns)

How to achieve this? Thanks.

Aritra Nath
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0 Answers0