numpy.matlib.eye(n, M=None, k=0, dtype=<type 'float'>, order='C')[源代码]

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

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.

order : {‘C’, ‘F’}, optional

Whether the output should be stored in row-major (C-style) or column-major (Fortran-style) order in memory.

1.14.0 新版功能.

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.


Equivalent array function.
Square identity matrix.


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