How do I transform a "SciPy sparse matrix" to a "NumPy matrix"?

python numpy scipy sparse-matrix networkx
Mr.Boy picture Mr.Boy · Oct 26, 2014 · Viewed 37.8k times · Source

I am using a python function called "incidence_matrix(G)", which returns the incident matrix of graph. It is from Networkx package. The problem that I am facing is the return type of this function is "Scipy Sparse Matrix". I need to have the Incident matrix in the format of numpy matrix or array. I was wondering if there is any easy way of doing that or not? Or is there any built-in function that can do this transformation for me or not?

Thanks

Answer

sebix picture sebix · Oct 26, 2014

The scipy.sparse.*_matrix has several useful methods, for example, if a is e.g. scipy.sparse.csr_matrix:

  • a.toarray() or a.A - Return a dense ndarray representation of this matrix. (numpy.array, recommended)
  • a.todense() or a.M - Return a dense matrix representation of this matrix. (numpy.matrix)

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