test_sparse

test_sparse.py

from scipy import sparse as sps
import numpy as np

z = np.arange(10)

N = len(z)

c = np.tile(z[:, None], (1, 10)).astype(int)
# Change some values:
c[:, 3] = 0
c[3, 7] = 100
c[3, 5] = 0
c[8, 8] = 30
c[7, 8] = 0

# Cast this into a sparse matrix:
a = sps.csc_matrix(c)

# Do the count in a loop:
count = 0
for i in range(N):
    count += (z == a[:, i]).sum()

print "The shape of '(z == a[:, i])' is: " + str((z == a[:, i]).shape)

print (a == z[:, None]).sum()
print count