1. Generalities

A NUME_DDLsert to define the numbering of the unknowns (and equations) of a linear system. We recall that the unknowns of such a system are components carried by nodes from MAILLAGE (or late nodes from LIGREL).

The matrices that we want to describe are square, sparse, symmetric or not.

When a matrix is non-symmetric, its sparse structure is symmetric.

The numbering of the unknowns of a system is similar to that of the components of a CHAM_NO. Moreover, SD NUME_EQUA described in this document is the one referenced by SD CHAM_NO [D4.06.05 - Field Data Structure].

SD NUME_DDLcontient also describes the arrays for storing values of assembled matrices [D4.06.10 - Structure de Données sd_matr_asse]. We call STOCKAGEcette part of the data structure.

Dependency relationships between these objects can be represented by:

Figure 1-a : Links of NUME_DDL, NUME_EQUA, and STOCKAGE to other data structures