numpy.ma.identity

numpy.ma.identity(n, dtype=None)

Return the identity array.

The identity array is a square array with ones on the main diagonal.

Parameters :

n : int

Number of rows (and columns) in n x n output.

dtype : data-type, optional

Data-type of the output. Defaults to float.

Returns :

out : ndarray

n x n array with its main diagonal set to one, and all other elements 0.

Examples

>>> np.identity(3)
array([[ 1.,  0.,  0.],
       [ 0.,  1.,  0.],
       [ 0.,  0.,  1.]])