Compute all the orthonormalized Legendre polynomials.

## Usage

call PlON (p, lmax, z, exitstatus)

## Parameters

p : output, real*8, dimension (lmax+1)
An array of orthonormalized Legendre polynomials up to degree lmax. Degree l corresponds to array index l+1.
lmax : input, integer
The maximum degree of the Legendre polynomials to be computed.
z : input, real*8
The argument of the Legendre polynomial.

## Description

PlON will calculate all of the orthonormalized Legendre polynomials up to degree lmax for a given argument. These are calculated using a standard three-term recursion formula. The integral of the orthonormalized normalized Legendre polynomials over the interval [-1, 1] is 2/(4pi).

exitstatus : output, optional, integer
If present, instead of executing a STOP when an error is encountered, the variable exitstatus will be returned describing the error. 0 = No errors; 1 = Improper dimensions of input array; 2 = Improper bounds for input variable; 3 = Error allocating memory; 4 = File IO error.