Qform2sph.m
Returns the spherical expansion coefficients of RT*A*R/R^2=Sum(rL(M)YLM). Parameters:
A - 3x3 matrix
Output:
[r0,r1,r2] - coefficients for zero, first, and second rank spherical
harmonics in the order -m:m
[r0,r1,r2]=qform2sph(A)