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.
Syntax
numpy.asmatrix(data, dtype=None)Parameters
data: (array_like)
We provide the input as an array to convert that into the matrix.
dtype:(data-type)
The data type of the resultant matrix, formed via the asmatrix function, is provided by default; it’s the same as the inputted data.
Return Value
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.
Example
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)
Output
[[1 2]
[3 4]]
Manipulating the matrix formed via asmatrix function
[[5 2]
[3 4]]
[[0.]
[0.]
[0.]]
That’s it.
