It computes the Normalized Associated Legendre Polynomials suitable for use in spherical harmonics
y = NormAss_legendre(l,m,x)
output
are integers. m greater than equal to 0 and l greater than equal to m.
is a real number lies in the range [-1,1]
This function computes the Normalized Associated Legendre Polynomial for given values of l, m and x.