Python | Numpy np.cheb2poly() method

With the help of np.cheb2poly() method, we can get the polynomial from chebyshev series by using np.cheb2poly() method.

Syntax : np.cheb2poly(array)
Return : Return array having coefficients of polynomial.

Example #1 :
In this example we can see that by using np.cheb2poly() method, we are able to get the polynomial from chebyshev series by using this method.

# import numpy
import numpy as np
from numpy import polynomial as P

x = np.array([2, 5, 7])

# using np.cheb2poly() method
gfg = P.Chebyshev(x)
gfg = gfg.convert(kind = P.Polynomial)
gfg = P.chebyshev.cheb2poly(gfg)

print(gfg)

[Polynomial([-5., 5., 14.], domain=[-1., 1.], window=[-1., 1.])]

Example #2 :

# import numpy
import numpy as np
from numpy import polynomial as P

x = np.array([2, 3, 5, 7, 11])

# using np.cheb2poly() method
gfg = P.Chebyshev(x)
gfg = gfg.convert(kind = P.Polynomial)
gfg = P.chebyshev.cheb2poly(gfg)

print(gfg)

[Polynomial([8., -18., -78., 28., 88.], domain=[-1., 1.], window=[-1., 1.])]