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Solve a system of linear equations (direct or iterative method)

The resolution methods implemented in*Code_Aster* and usable by this command are:

1. method MULT_FRONT (direct method),

2. method LDLT (direct method),

3. the MUMPS method (direct method),

4. the GCPC method (iterative method),

5. the PETSC method (iterative method).

The effective choice of the method is made through the command FACTORISER [U4.55.01].

For direct methods, the matrix must have been factorized beforehand using the FACTORISER [U4.55.01] command. In the case of iterative methods with preconditioning, the preconditioning matrix is also provided by the operator FACTORISER [U4.55.01].

The operator allows complex resolutions for « direct » methods (not for iterative methods).

Produces a data structure of type cham_no.