numpy.polynomial.chebyshev.chebfromroots(roots)
[source]
Generate a Chebyshev series with given roots.
The function returns the coefficients of the polynomial
in Chebyshev form, where the r_n
are the roots specified in roots
. If a zero has multiplicity n, then it must appear in roots
n times. For instance, if 2 is a root of multiplicity three and 3 is a root of multiplicity 2, then roots
looks something like [2, 2, 2, 3, 3]. The roots can appear in any order.
If the returned coefficients are c
, then
The coefficient of the last term is not generally 1 for monic polynomials in Chebyshev form.
Parameters: |
|
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Returns: |
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See also
polyfromroots
, legfromroots
, lagfromroots
, hermfromroots
, hermefromroots
>>> import numpy.polynomial.chebyshev as C >>> C.chebfromroots((-1,0,1)) # x^3 - x relative to the standard basis array([ 0. , -0.25, 0. , 0.25]) >>> j = complex(0,1) >>> C.chebfromroots((-j,j)) # x^2 + 1 relative to the standard basis array([1.5+0.j, 0. +0.j, 0.5+0.j])
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https://docs.scipy.org/doc/numpy-1.17.0/reference/generated/numpy.polynomial.chebyshev.chebfromroots.html