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chebcoefs()

Usage:
chebcoefs(vector(a0,a1,...,an)), a0, a1, ..., an non MISSING REAL
  scalars



Keywords: expansions, power series, orthogonal polynomials
                                  Usage
Suppose Pn(x) = a0+a1*x+ ... + an*x^n is a polynomial in x of degree
n.  Then Pn(x) has a unique expansion, Pn(x) = b0 + b1*T1(x) + ... +
bn*Tn(x), where Tj(x) = the Chebyshev polynomial of degree j defined
for -1 <= x <= 1 as Tj(x) = cos(j*acos(x)).

chebcoefs(vector(a0,a1,...,an)), where a0, a1, ..., an are non MISSING
REAL scalars returns vector(b0,b1,...,bn), where the b's are the
coefficients in the Chebyshev expansion.

                             Cross reference
See also topic invchebcoefs().


Gary Oehlert 2006-01-30