numpy.matlib.eye() — another function to do matrix operations in numpy. Returns a matrix with diagonal ones and zeros elsewhere.
Syntax: numpy.matlib.eye (n, M = None, k = 0, dtype = ` float `, order =` C `)
n: [int] Number of rows in the output matrix.
M: [int, optional] Number of columns in the output matrix, defaults is 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. Default is 0.
dtype: [optional] Desired output data-type .
order: Whether to store multi-dimensional data in row-major (C-style) or column-major (Fortran-style) order in memory.
Return: A nx M matrix where all elements are equal to zero, except for the k-th diagonal, whose values are equal to one.
Code # 1:
Output matrix: [[1.0.0 .] [0. 1. 0.] [0. 0. 1.]]
Code # 2:
Output matrix: [[0 1 0 0 0] [0 0 1 0 0] [0 0 0 1 0] [0 0 0 0 1]]