[FIXED] add rows with inverted values for two way relationship in pandas

Issue

I have this df:

   Source   Target  Relationship
1   C0003   C0007   Spouse
2   C0004   C1501   Spouse
3   C0042   C1931   Spouse

which contains IDs of married couples. Now I need to duplicate each row so that Each person of the couple is both a Source and a Target, the final outcome should be this:

   Source   Target  Relationship
1   C0003   C0007   Spouse
4   C0007   C0003   Spouse
2   C0004   C1501   Spouse
5   C1501   C0004   Spouse
3   C0042   C1931   Spouse
6   C1931   C0042   Spouse

Thanks in advance for your help!

Solution

You can create a new data frame with column Source as Target and Target as Source, and then append it to the original data frame:

df.append(df.rename(columns={'Source': 'Target', 'Target': 'Source'})).sort_index()

#  Source Target Relationship
#1  C0003  C0007       Spouse
#1  C0007  C0003       Spouse
#2  C0004  C1501       Spouse
#2  C1501  C0004       Spouse
#3  C0042  C1931       Spouse
#3  C1931  C0042       Spouse
#4  C0052  C0932       Spouse
#4  C0932  C0052       Spouse
#5  C0054  C1784       Spouse
#5  C1784  C0054       Spouse

Answered By - Psidom