The numpy.asmatrix() function “interprets the input as a matrix”. If the input is already a matrix or a ndarray of 2 dimensions, it returns the input as is. If the input is a different data type, such as a list or a tuple, it converts it into a matrix.
We provide the input as an array to convert that into the matrix.
The data type of the resultant matrix, formed via the asmatrix function, is provided by default; it’s the same as the inputted data.
It takes the inputted array and converts that into a matrix. It doesn’t make a copy of a matrix, or ndarray is passed to it. The data type of the output matrix is the same as the inputted array.
import numpy as np x = np.array([[1, 2], [3, 4]]) m = np.asmatrix(x) print(m) print('Manipulating the matrix formed via asmatrix function') x[0, 0] = 5 print(m) a = np.asmatrix(np.zeros((3, 1))) print(a)
[[1 2] [3 4]] Manipulating the matrix formed via asmatrix function [[5 2] [3 4]] [[0.] [0.] [0.]]