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Given the following text problem statement, write Python code to implement the functionality described below in problem statement
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Problem:
Suppose I have a integer matrix which represents who has emailed whom and how many times. I want to find people that have not emailed each other. For social network analysis I'd like to make a simple undirected graph. So I need to convert the matrix to binary matrix.
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Python Code:
import scipy
import numpy as np
a = np.array([[26, 3, 0], [3, 195, 1], [0, 1, 17]])
a = 1-np.sign(a)
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