  # Python | Numpy np.chebvander2d () method

NumPy | Python Methods and Functions

Using the `np.chebvander2d() ` method we can get a 2D Pseudo-Vandermonde matrix from a given array, the degree of which is passed as a parameter using ` np .chebvander2d () `.

Syntax: ` np.chebvander2d (x, y, degree) `
Return: Return the 2D matrix having size ie array.size + (degree + 1).

Example # 1:
In this example, we can see that with ` np.chebvander2d () ` we can get a 2D pseudo-vandermonde matrix using this method.

 ` # NumPy import ` ` import ` ` numpy as np ` ` import ` ` numpy.polynomial.chebyshev as cheb `   ` # using the np.chebvander2d () method ` ` gfg ` ` = ` ` cheb.chebvander2d ((` ` 2 ` `, ` ` 4 ` `, ` ` 8 ` `, ` ` 1 ` `), (` ` 2 ` `, ` ` 4 ` `, ` ` 8 ` `, ` ` 1 ` `), ` ` 2 ` `) `   ` print ` ` (gfg) `

Exit:

[[1. 2. 7.]
[1. 4. 31.]
[1. 8. 127.]
[1. 1. 1.]]

Example # 2:

 ` # NumPy import ` ` import ` ` numpy as np ` ` import ` ` numpy.polynomial.chebyshev as cheb `   ` # using the method np.chebvander2d () ` ` gfg ` ` = ` ` cheb.chebvander2d ((` ` 3 ` `, ` ` 5 ` `, ` ` 1 ` `, ` ` 10 ` `), (` ` 3 ` `, ` ` 5 ` `, ` ` 1 ` `, ` ` 10 ` `), ` ` 4 ` `) `   ` print (gfg) `

Output:

[[1.0000e + 00 3.0000e + 00 1.7000e + 01 9.9000e + 01 5.7700e + 02]
[1.0000e + 00 5.0000e + 00 4.9000e + 01 4.8500e + 02 4.8010e + 03]
[1.0000e + 00 1.0000e + 00 1.0000e + 00 1.0000e + 00 1.0000e + 00]
[1.0000 e + 00 1.0000e + 01 1.9900e + 02 3.9700e + 03 7.9201e + 04]]