orthopolynom (version 1.0-5)

glaguerre.inner.products: Inner products of generalized Laguerre polynomials

Description

This function returns a vector with \(n + 1\) elements containing the inner product of an order \(k\) generalized Laguerre polynomial, \(L_n^{\left( \alpha \right)} \left( x \right)\), with itself (i.e. the norm squared) for orders \(k = 0,\;1,\; \ldots ,\;n \).

Usage

glaguerre.inner.products(n,alpha)

Arguments

n

integer highest polynomial order

alpha

polynomial parameter

Value

A vector with \(n + 1\) elements

1

inner product of order 0 orthogonal polynomial

2

inner product of order 1 orthogonal polynomial

...
n+1

inner product of order \(n\) orthogonal polynomial

Details

The formula used to compute the inner products is as follows.

\(h_n = \left\langle {L_n^{\left( \alpha \right)} |L_n^{\left( \alpha \right)} } \right\rangle = \frac{{\Gamma \left( {\alpha + n + 1} \right)}} {{n!}}\).

References

Abramowitz, M. and I. A. Stegun, 1968. Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables, Dover Publications, Inc., New York.

Courant, R., and D. Hilbert, 1989. Methods of Mathematical Physics, John Wiley, New York, NY.

Szego, G., 1939. Orthogonal Polynomials, 23, American Mathematical Society Colloquium Publications, Providence, RI.

Examples

Run this code
# NOT RUN {
###
### generate the inner products vector for the
### generalized Laguerre polynomial inner products of orders 0 to 10
### polynomial parameter is 1.
###
h <- glaguerre.inner.products( 10, 1 )
print( h )
# }

Run the code above in your browser using DataCamp Workspace