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Legendre Module (`numpy.polynomial.legendre`)

# numpy.polynomial.chebyshev.poly2cheb

`numpy.polynomial.chebyshev.``poly2cheb`(pol)

  Convert a polynomial to a Chebyshev series.

  Convert an array representing the coefficients of a polynomial (relative to the “standard” basis) ordered from lowest degree to highest, to an array of the coefficients of the equivalent Chebyshev series, ordered from lowest to highest degree.

  Parameters: | pol : array_like 1-D array containing the polynomial coefficients
  Returns: | c : ndarray 1-D array containing the coefficients of the equivalent Chebyshev series.

  See also

  `cheb2poly`

  Notes

  The easy way to do conversions between polynomial basis sets is to use the convert method of a class instance.

  Examples

      >>> from numpy import polynomial as P
      >>> p = P.Polynomial(range(4))
      >>> p
      Polynomial([ 0.,  1.,  2.,  3.], [-1.,  1.])
      >>> c = p.convert(kind=P.Chebyshev)
      >>> c
      Chebyshev([ 1.  ,  3.25,  1.  ,  0.75], [-1.,  1.])
      >>> P.poly2cheb(range(4))
      array([ 1.  ,  3.25,  1.  ,  0.75])