Python稀疏矩阵运算

 1 import numpy as np
 2 import scipy
 3 import time
 4 import scipy.sparse as sparse
 5 
 6 t = [1]+[0]*4999
 7 a = scipy.matrix(np.array(t*5000, dtype=float).reshape(5000, 5000))
 8 start = time.time()
 9 b = np.dot(a, a)
10 print(time.time() - start)
11 
12 start = time.time()
13 aa = sparse.coo_matrix(a)
14 b = np.dot(aa, aa).todense()
15 print(time.time() - start)