XLPack 7.0
XLPack Numerical Library (Excel VBA) Reference Manual
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◆ Jacobi_sub()

Sub Jacobi_sub ( Ret As  Double,
N As  Long,
Alpha As  Double,
Beta As  Double,
X As  Double,
Optional Info As  Long 
)

Jacobi polynomial Pn(α, β)(x) (Subroutine version)

Purpose
Computes the Jacobi polynomial.
The Jacobian polynomial Pn(α, β)(x) is an orthogonal polynomial defined on the interval [-1, 1] with a weight function w(x) = (1 - x)^α (1 + x)^β.
The Jacobi polynomial satisfies the following three term recurrence relation.
P0(α, β)(x) = 1
P1(α, β)(x) = (1/2)((α + β + 2)x + (α - β))
Pn(α, β)(x) = (1/(2n(n + α + β)(2n + α + β - 2)))((2n + α + β - 1)((2n + α + β - 2)(2n + α + β)x + (α^2 - β^2))P(n - 1)(α, β)(x) - 2(n + α - 1)(n + β - 1)(2n + α + β)P(n - 2)(α, β)(x))
Parameters
[out]RetJacobi polynomial Pn(α, β)(x).
[in]NDegree of polynomial n. (N >= 0)
[in]AlphaParameter α.
[in]BetaParameter β.
[in]XArgument x.
[out]Info(Optional)
= 0: Successful exit.
= -1: The argument N had an illegal value. (N < 0)
= 1: Floating point range error.
Reference
boost/math/special_functions