Rank Deficient
Rank Deficient
(OP)
I am running an extensive FEMAP model and I keep getting the following errors:
*** USER WARNING MESSAGE 6137 (UDSNRD)
INPUT MATRIX IS RANK DEFICIENT, RANK = 12720 IERROR
USER ACTION: CHECK MODEL
User information:
One of your matrices is singular. See the NX NASTRAN Numerical
Methods User's Guide. for a discussion of singularity.
*** USER FATAL MESSAGE 6202 (MCE1)
THE SELECTED MULTIPOINT CONSTRAINT SET AND/OR RIGID ELEMENTS PRODUCE A SINGULAR RMM MATRIX. THIS MAY BE CAUSED BY A
CIRCULAR DEPENDENCY IN WHICH A DEGREE OF FREEDOM IS INDIRECTLY DEPENDENT UPON ITSELF.
*** USER FATAL MESSAGE 3005 (MCE1)
ATTEMPT TO OPERATE ON THE SINGULAR MATRIX SCRATCH IN SUBROUTINE MCE1
User information:
Subroutine SDCOMP or subroutine UDCOMP has detected a singular
matrix and the calling routine does not support this case.
A User Information Message defining the singularity has already
been printed.
0FATAL ERROR
1
It is telling me I have a singularity somewhere. Can anybody help on how to find this singularity in a quick, easy and efficient manner? Any suggestions are welcome.
*** USER WARNING MESSAGE 6137 (UDSNRD)
INPUT MATRIX IS RANK DEFICIENT, RANK = 12720 IERROR
USER ACTION: CHECK MODEL
User information:
One of your matrices is singular. See the NX NASTRAN Numerical
Methods User's Guide. for a discussion of singularity.
*** USER FATAL MESSAGE 6202 (MCE1)
THE SELECTED MULTIPOINT CONSTRAINT SET AND/OR RIGID ELEMENTS PRODUCE A SINGULAR RMM MATRIX. THIS MAY BE CAUSED BY A
CIRCULAR DEPENDENCY IN WHICH A DEGREE OF FREEDOM IS INDIRECTLY DEPENDENT UPON ITSELF.
*** USER FATAL MESSAGE 3005 (MCE1)
ATTEMPT TO OPERATE ON THE SINGULAR MATRIX SCRATCH IN SUBROUTINE MCE1
User information:
Subroutine SDCOMP or subroutine UDCOMP has detected a singular
matrix and the calling routine does not support this case.
A User Information Message defining the singularity has already
been printed.
0FATAL ERROR
1
It is telling me I have a singularity somewhere. Can anybody help on how to find this singularity in a quick, easy and efficient manner? Any suggestions are welcome.





RE: Rank Deficient
RE: Rank Deficient
RE: Rank Deficient
RE: Rank Deficient
good luck !
RE: Rank Deficient
RE: Rank Deficient
good luck !
RE: Rank Deficient
RE: Rank Deficient
-Nathan
RE: Rank Deficient
Simply edit the nastran input deck and in the bulk data section write "param,bailout,-1" and solve the model. If you have a singular matrix because your model is not properly constrained (you have rigid body motions) then the nx nastran solver will run with sucess. Later go to postprocessor and see displacements results, surely you will see values of meters o km, not problem, the important is that you see where the error is, you locate this way the piece that is unconstrained, simply define constrains properly and launch the solver again, and now I hope with success.
Let me know if this helps to solve your problem.
Best regards,
Blas.