NX Nastran DMAP Programmer's Guide - Kxcad.net

886
DECOMP
Matrix decomposition
Examples:
1. Solve [A][X] = [B].
DECOMP A/L,U,/ $
FBS L,U,B/X/ $
MATPRN X// $
2. Form [K] = [G] T [A][G].
Then decompose [K] into [L] [L] T assuming [K] is a symmetric matrix.
SMPYAD G,A,G,,,/K/3////1////6 $
DECOMP K/L,,/ $
– 1
Koa
3. Calculate Kaa Kaa – Kao Koo using partial decomposition, then form
given the following:
• NOOSET integer parameter defining the size of Koo .
• NOASET integer parameter defining the size of Kaa • NOFSET = NOOSET + NOASET
and Koa .
= L oo
$ FORM PARTITIONING VECTOR
MATGEN ,/VFOX/6/NOFSET/NOOSET/NOASET $
$ MERGE O-SET AND A-SET WITH A-SET LAST
MERGE KOO,KAO,KOA,KAAB,VFOX,/KFFX/-1/0/6 $
$ PARTIALLY DECOMPOSE KFFX
DECOMP KFFX/LFO,KAA,/3/NOOSET $
PARTN LFO, ,VFOX/LOO, LAO, ,/1 $