Implemented the collection of the 3D exchange matrix, for rank [NE][NS][NM][NO][ND][7][7].
Task #7807 (https://gna.org/task/index.php?7807): Speed-up of dispersion models for Clustered analysis.
Authored by: tlinnet 2014-06-19
Parent: [r24150]
Child: [r24152]
