User Area > Advice
Typical error message from LUSAS Solver text output file (*.OUT)
***** PROCESS ERROR REPORTED BY SUBROUTINE xdseex
SEE xdseex ABSTRACT (IER = -711)
***ERROR*** NO EIGENVALUES FOUND (BCSESV PROCESSOR)
or
***ERROR*** EIGENVALUE
EXTRACTION UNSUCCESSFUL : INTERNAL ERROR ENCOUNTERED WITH CODE -711 IN ROUTINE xdseex
Most common causes & links to solutions
Errors less than zero indicate that no eigenvalues were
able to be extracted at all prior to the error. Positive
values indicate that the eigenvalue extraction was at least
partly successful prior to the error.
The structure may be inadequately supported, have element mechanisms or mesh discontinuities, or the geometric/material properties may be incorrectly idealised.
Where this error occurs, it
is recommended that a linear static analysis is carried out using the standard
Frontal Solver (set via File menu
> Model Properties > Solution tab >
Solver Options) to identify and potential modelling problems that may cause failed convergence.
There is a cursory checklist
which is applicable to linear static analyses. It has only 5 points but is very instructive in identifying problems in models.
If Solver has a license for
running Fast Solvers, then the Eigensolver could be set to
the standard default "Subspace Jacobi" in the
Eignevnalue control as an alternaive Eigensolver that
(although slower) will do more checks on the problem
defined, reporting any warnings or errors found, which may
give clues as to where the problem lies.
Please also see the following reference for further
information:
Help menu > Help
Topics > Contents > Modeller Reference Manual >
Appendix B : LUSAS Solver Trouble Shooting > When an Eigenvalue Analysis Goes Wrong
Alternatively, the message may be caused by an input/output error when reading
or writing from/to the fast eigensolver scratch files.
There are several reasons why your PC may generate such an
error, these are listed with suitable solutions below:
Model problems may cause files to become
larger than necessary
-
Eliminate
modelling problems which trigger warnings in your *.OUT file
-
Check
mesh refinement
(reduce number of elements if appropriate)
PC settings may cause temporary files to clash
with virtual memory
-
Relocate
or re-size PC virtual memory
-
Relocate
LUSAS temporary files
-
Relocate
Windows temporary files
-
Optimise
LUSAS memory usage
(reduce cache/ NPGS)
PC hard drive may be getting full
-
Clear
temporary files
-
Reduce
the size of eigenvalue analysis files
-
Reduce
the size of the results file
(*.MYS)
PC hardware is inadequate for the size of
problem
-
Upgrade
PC hardware
More on cause & theory links
During solution LUSAS uses temporary files and also produces
*.OUT and *.MYS files. In large models, these files can be of
significant size (up to 8GB is possible) and they may take up
space on the disk, limiting space available for the operating system
swap/ page
file. Solutions relevant to this particular problem are
among those listed above.
More on how LUSAS uses PC
resources
This message can also occur because the
maximum amount of memory that is available to Solver that it can
use is not enough for the problem defined. Reducing the
number of elements or Eigenvalues to be returned will help in
this case, otherwise 64bit Solver and/ore more physical memory
on the PC may help.
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