`scipy.io._mmio:mmread`

Signature

def mmread(source, *, spmatrix = <object object at 0x0000>)

Reads the contents of a Matrix Market file-like 'source' into a matrix.

source : str or file-like: Matrix Market filename (extensions .mtx, .mtz.gz) or open file-like object.
spmatrix : bool, optional (default: True): If True, return sparse matrix. Otherwise return sparse array.
deprecated 1.18.0
The default value for spmatrix is changing to False in v2.1. That means the default return value will be a sparse array. Unless you use * instead of @, ** for matrix power, or you depend on 2D shapes from e.g. A.sum(axis=0) it may not matter to you. See Migration from spmatrix to sparray.
deprecated 2.0.0
The value True for spmatrix will no longer be supported in v2.2. The spmatrix classes are deprecated and will be removed then.

a : ndarray or coo_array or coo_matrix: Dense or sparse array depending on the matrix format in the Matrix Market file.

from io import StringIO
from scipy.io import mmread

✓

text = '''%%MatrixMarket matrix coordinate real general
 5 5 7
 2 3 1.0
 3 4 2.0
 3 5 3.0
 4 1 4.0
 4 2 5.0
 4 3 6.0
 4 4 7.0
'''

✓

``mmread(source)`` returns the data as sparse matrix in COO format.

m = mmread(StringIO(text), spmatrix=False)

✓

✗

<COOrdinate sparse array of dtype 'float64'
	with 7 stored elements and shape (5, 5)>

m.toarray()

✓

array([[0., 0., 0., 0., 0.],
       [0., 0., 1., 0., 0.],
       [0., 0., 0., 2., 3.],
       [4., 5., 6., 7., 0.],
       [0., 0., 0., 0., 0.]])