Python NumPy 和 SciPy - .todense() 和 .toarray() 之间的区别
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NumPy and SciPy - Difference between .todense() and .toarray()
提问by
I am wondering if there is any difference (advantage/disadvantage) of using .toarray()vs. .todense()on sparse NumPy arrays. E.g.,
我想知道在稀疏 NumPy 数组上使用.toarray()与使用是否有任何区别（优势/劣势）.todense()。例如，
import scipy as sp
import numpy as np
sparse_m = sp.sparse.bsr_matrix(np.array([[1,0,0,0,1], [1,0,0,0,1]]))
%timeit sparse_m.toarray()
1000 loops, best of 3: 299 μs per loop
%timeit sparse_m.todense()
1000 loops, best of 3: 305 μs per loop
采纳答案by user2357112 supports Monica
toarrayreturns an ndarray; todensereturns a matrix. If you want a matrix, use todense; otherwise, use toarray.
toarray返回一个 ndarray；todense返回一个矩阵。如果你想要一个矩阵，请使用todense; 否则，使用toarray.
