# Computational Topology - Vietoris-Rips Complex Graph

Write code in Python for the function RipsGraph(P,d) as follows.

- Inputs:

- P : a set of points P belonging to R2 given as a k x 2 numpy matrix
- d : a diameter d >= 0

-Output:

- a networkx graph which is the 1-skeleton of the Rips complex VR(P, d).

Create a point set of 15 random points in the box [0, 1]x[0, 1]. Draw this graph as an overlay on the points.

Note: I have little to no programming skills, so I'm just learning. Please bear with me.

Here's my work so far:

import numpy as np
import networkx as nx
P = np.random.random((15,2)) #each point is row in matrix
from scipy.spatial import distance-matrix
plt.matshow(distance-matrix(P,P))
row,col = np.where(D<???) #must find point with distance <???... not sure what distance to use
print(row[:10],'\n',col[:10]) - slicing matrix

#Next, I must remove duplicates and any point where col>row.. by slicing the matrix with specific parameters..
#Then, I must tell networkx where I want the vertices, so it can produce the edges for the 1-skeleton

Any help is greatly appreciated. Thanks!

Last edited by moh533; Sep 15, 2017 at 06:55 AM. Reason: Forgot to add work
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 smoothy Posts: 25,497, Reputation: 2853 Uber Member #2 Sep 14, 2017, 09:36 PM
Homework rules on this site REQUIRE you provide your works AND what you think the answer is. You forgot to cut and paste those.
 moh533 Posts: 5, Reputation: 1 New Member #3 Sep 15, 2017, 06:55 AM
Woops, sorry about that. Just edited it.

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