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5 Finite Element Interface (FEI)

 

The finite element interface (FEI) defines a linear solver interface for finite element applications. For information on how to use this interface, see [&make_named_href('', "node39.html#FEI-ref","[4]")]. This chapter describes the iterative methods and preconditioners in the HYPRE implementation of this interface.

Solving a linear system from a finite element problem consists of four steps in the FEI:

  1. Initialize the structure of the finite-element data, including loading the element connectivity data
  2. Load the element or super-element stiffness matrices and forcing terms
  3. Set solver parameters and solve the linear system
  4. Retrieve the solution to the linear system

Parameters to the HYPRE solvers are specified by calling

void FEI_parameters(int sysHandle, int numParams, char **paramStrings);
where sysHandle is an identifier for the linear system being solved, numParams is the number of parameter strings, and paramStrings is an array of null-terminated strings with the format: ``parameter_name value''. For example, setting the preconditioner can be accomplished by:
char **paramStrings[1];
paramStrings[0] = (char *) malloc(64*sizeof(char));
strcpy(paramStrings[0], "preconditioner parasails");
FEI_parameters(sysHandle, 1, paramStrings);
All possible parameters are listed in Table 5.1.

A linear system is then solved by calling

void FEI_iterateToSolve(int sysHandle);



next up previous contents index
Next: 5.1 Iterative methods and Up: User's Manual Previous: 4.5 Setting Up the

Thomas Treadway
Fri Jul 27 10:01:25 PDT 2001