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scipy.sparse.identity

scipy.sparse.identity(n, dtype='d', format=None)

Identity matrix in sparse format

Returns an identity matrix with shape (n,n) using a given sparse format and dtype.

Parameters :

n : integer

Shape of the identity matrix.

dtype : :

Data type of the matrix

format : string

Sparse format of the result, e.g. format=”csr”, etc.

Examples

>>> identity(3).todense()
matrix([[ 1.,  0.,  0.],
        [ 0.,  1.,  0.],
        [ 0.,  0.,  1.]])
>>> identity(3, dtype='int8', format='dia')
<3x3 sparse matrix of type '<type 'numpy.int8'>'
        with 3 stored elements (1 diagonals) in DIAgonal format>