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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>

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