[igraph] Python iGraph: Create graph from numpy / pandas dataframe

[Nick Eubank]

Hell All,

I'm trying to figure out the most efficient way of creating an igraph object form an edgelist stored in a numpy array (or rather, technically, a pandas DataFrame). 

The DataFrame looks something like:

    a        b           weight

    100    101       1

    100    102       5

    101    103       1

    101    104       4

The numbers in a and b are NOT sequential integers, though I can write code to make those conversion if necessary. 

One option is obviously to write out the data frame as a text file, then re-import as an ncol or such. But my dataset is very large (the edgelist has about 400,000,000 entries), which means that's a massively slow process, and I think loading the text file when importing into igraph may be requiring more ram than I have. 

I've found resources on importing adjacency matrices, but nothing on edgelists. 

Anyone run into this before / have any suggestions?

Thanks!

Nick