  # Python | The numpy np.chebval () method

NumPy | Python Methods and Functions

Using the `np.chebval() ` method, we can get an array of coefficients after calculating x on Chebyshev series using ` np.chebval () ` .

Syntax: ` np.chebval (x, c) `
Return: Return an array after evaluation on x.

Example # 1:
In this example we can see that with ` np.chebval () ` we can get an array of coefficients by calculating x along the Chebyshev row.

 ` # NumPy import ` ` import ` ` numpy as np ` ` import ` ` numpy.polynomial.chebyshev as cheb `   ` # using the method np.chebval () ` ` gfg ` ` = ` ` cheb.chebval ((` ` 2 ` `, ` ` 5 ` `), (` ` 2 ` `, ` ` - ` ` 4 ` ` , ` ` 1 ` `)) `   ` print ` ` (gfg) `

Output:

[1. 31.]

Example # 2:

 ` # NumPy import ` ` import ` ` numpy as np ` ` import ` ` numpy.polynomial.chebyshev as cheb `   ` # using the np.chebval () method ` ` gfg ` ` = ` ` cheb.chebval ((` ` 1 ` `, ` ` 3 ` `, ` ` 5 ` `, ` ` 7 ` `) , (` ` 2 ` `, ` ` - ` ` 4 ` `, ` ` 1 ` `, ` ` 5 ` `, ` ` 1 ` `)) `   ` print ` ` (gfg ) `

Output:

[5.0000e + 00 1.0790e + 03 7.2570e + 03 2.5643e + 04]