| E5007 | FATAL ERROR: E5007 | MASS MATRIX NON-POSITIVE DEFINITE |
| Cause: | A non-positive definite has been detected in the mass matrix during the preconditioning phase of the Lanczos eigensolver solver. If you also have a T2062 warning message, then the error is due to a non-positive definite element mass matrix. | |
| Action: | If there are mass elements specified in the model, make sure the mass matrix defined is positive definite. Also, make sure all densities specified on material property entries are positive. | |
| Remarks: | See Autodesk Nastran Reference Guide, Section 4, Bulk Data, for entry format. |