1. Generalities

The sd_matr_asse objects represent square assembled matrices (in the sense of finite elements). They are generally large objects. These matrices are sparse, which is why their structure is not simply a square array.

An sd_matr_asse can come from an assembly of sd_matr_elem or from a linear combination of other sd_matr_asse.

The tables describing the storage of the sd_matr_asse are in the sd_storage structure of an sd_nume_ddl [D4.06.07].

There are symmetric sd_matr_asse and non-symmetric sd_matr_asse. But it is assumed that the topology of the matrix is always symmetric. That is to say that the non-zero terms are arranged symmetrically with respect to the diagonal.