NumPy and SciPy - Difference between .todense() and .toarray()

I am wondering if there is any difference (advantage/disadvantage) of using .toarray() vs. .todense() on sparse NumPy arrays. E.g.,

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

1 Answer

toarray returns an ndarray; todense returns a matrix. If you want a matrix, use todense; otherwise, use toarray.