Problem Description
An error "Singular matrix" occurs.
Solution
The system matrix (Jacobian matrix or stiffness matrix) is singular, so the solver cannot invert it. Usually this means that the system is underdetermined. Check that all equations are fully specified and that the boundary conditions are appropriate. For instance, in a stationary model you usually need to have a Dirichlet condition on some boundary (that is, specifying the value of the solution on the boundary).
A singular matrix could also occur if mesh elements are of too low quality. If the minimum element quality is less than 0.005 you might be in trouble (to check the mesh quality, plot the built-in variable qual). Another reason for this error message is that you have different element orders for two variables that are coupled by, for example, a weak constraint. Use the same element order for all variables that are coupled.
Recherche par catégorie
Messages d'erreur (65)Import (10)
Géométrie (14)
Physiques (10)
Solveur (35)
Installation (40)
Maillage (14)
Général (34)
Mécanique des structures (2)
Mécanique des fluides (1)
Post-traitement (4)
Export (1)
Dessin (1)
Informations produit (6)
Multiphysique (1)
Modèles utilisateurs (1)
Electromagnétisme (1)
COMSOL makes every reasonable effort to verify the information you view on this page. Resources and documents are provided for your information only, and COMSOL makes no explicit or implied claims to their validity. COMSOL does not assume any legal liability for the accuracy of the data disclosed. Any trademarks referenced in this document are the property of their respective owners. Consult your product manuals for complete trademark details.