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# numpy.matlib.eye

`numpy.matlib.``eye`(n, M=None, k=0, dtype=<type 'float'>)

  Return a matrix with ones on the diagonal and zeros elsewhere.

  Parameters: | n : int Number of rows in the output. M : int, optional Number of columns in the output, defaults to n. k : int, optional Index of the diagonal: 0 refers to the main diagonal, a positive value refers to an upper diagonal, and a negative value to a lower diagonal. dtype : dtype, optional Data-type of the returned matrix.
  Returns: | I : matrix A n x M matrix where all elements are equal to zero, except for the k-th diagonal, whose values are equal to one.

  See also

  `numpy.eye`
    Equivalent array function.
  `identity`
    Square identity matrix.

  Examples

      >>> import numpy.matlib
      >>> np.matlib.eye(3, k=1, dtype=float)
      matrix([[ 0.,  1.,  0.],
              [ 0.,  0.,  1.],
              [ 0.,  0.,  0.]])