{n} f(x_{n}).

This function returns the set of abscissae and weights

    {x_{n}, w_{n}}^{N}_{n=1}

for performing this calculation given N, the number of abscissae.
These abscissae correspond to the zeros of the Nth Hermite
polynomial.  It can be shown that such integration is exact when f(x)
is a polynomial of maximum order 2N-1.

The procedure in this calculation is taken more or less directly from

@BOOK{ press-etal-1992a,
	AUTHOR    = { Press, William  H.   and 
                Flannery, Brian  P.  an