Answers for "scipy sparse matrix operations"

sparse matrix representation python use

import numpy as np
from scipy.sparse import csr_matrix

# create a 2-D representation of the matrix
A = np.array([[1, 0, 0, 0, 0, 0], [0, 0, 2, 0, 0, 1],
 [0, 0, 0, 2, 0, 0]])
print("Dense matrix representation: n", A)

# convert to sparse matrix representation 
S = csr_matrix(A)
print("Sparse matrix: n",S)

# convert back to 2-D representation of the matrix
B = S.todense()
print("Dense matrix: n", B)

csr_matric scipy lib

>>> import numpy as np
>>> from scipy.sparse import csr_matrix
>>> csr_matrix((3, 4), dtype=np.int8).toarray()
array([[0, 0, 0, 0],
       [0, 0, 0, 0],
       [0, 0, 0, 0]], dtype=int8)