RDC refinement, via gyration tensor
 

Hi,

I am trying to find an alignment tensor for my RNA molecule.
This I want to do by calculating the gyration tensor, and derive the alignment tensor.

like in J. Biomol. NMR (2006) 35, pp. 103-115

problem is to do relatively simple manipulations in xplor
For example calculate the product of x-coordinate times y-coordinates of all atoms in the PDB file.

And probably diagonalizing it, or calculating eigenvalues will also be a problem.

Anyone an idea how to do this ?

Note: I am not using pyXplor, nor CNS/DYANA.
Just the old xplor v3.851

Regards,
Ramon