# How to create an adjacency matrix of mutual friendships from facebook in python

## Question:

I am doing a project on Social Network Analysis of Facebook Network. I had to get all my friends and who of my friends are friends with each other, mutual frindships inside my network. I did that, I got all id’s of my friends and adjacencies and now I have to form an adjacency matric which indicates if 2 of my friends are friends. For example:

A and B are friends, A and C are friends, but B and C are not friends. This would look like this:

```
A B C
A 0 1 1
B 1 0 0
C 1 0 0
```

Because I have the list of id’s and adjacencies already in python, I should also do the matrix in python, so if you have any ideas or a basic algorithm how to enter 1’s and 0’s I would appreciate it.

## Answers:

I think this structure is better implemented as a graph. For example, take a look at NetworkX.

Anyway, if you really need matrices, a matrix can simply be implement as a list of lists, like this:

```
m = [[0, 1, 1],
[1, 0, 0],
[1, 0, 0],]
```

But if you intend to do any matrix manipulation, you should check out the numpy library.

I solved the problem, it just required 2 for loops to go thorugh the list and compare whether the users id is in the adjacency list, if that is the case, make that entry 1, otherwise 0.