Question

I am new to python, and have a question regarding store columns in lists and converting them to dictionary as follow:

I have a data in two column shown below, with nodes(N) and edges(E), and I want to first make a list of these two columns and then make a dictionary of those two lists as

{1:[9,2,10],2:[10,111,9],3:[166,175,7],4:[118,155,185]}.

How can I do that? Thanks.

N   E           
1   9       
1   2       
1   10      
2   10      
2   111     
2   9       
3   166     
3   175     
3   7       
4   118     
4   155     
4   185

Answer 1

A defaultdict is a subclass of dict which would be useful here:

import collections
result=collections.defaultdict(list)
for n,e in zip(N,E):
    result[n].append(e)