mesh_from_tetgen_poisson.cc File Reference

#include "generic.h"
#include "poisson.h"
#include "meshes/tetgen_mesh.h"

Classes
class	PoissonProblem< ELEMENT >
	Micky mouse Poisson problem. More...

Namespaces
	TanhSolnForPoisson
	Namespace for exact solution for Poisson equation with "sharp step".

Functions
void	TanhSolnForPoisson::get_exact_u (const Vector< double > &x, Vector< double > &u)
	Exact solution as a Vector. More...
void	TanhSolnForPoisson::get_exact_u (const Vector< double > &x, double &u)
	Exact solution as a scalar. More...
void	TanhSolnForPoisson::get_source (const Vector< double > &x, double &source)
	Source function to make it an exact solution. More...
int	main (int argc, char *argv[])
	Demonstrate how to solve Poisson problem. More...

Function Documentation

main()

int main	(	int argc	,
		char *	argv[]
	)

Demonstrate how to solve Poisson problem.

{
 
// Store command line arguments
 CommandLineArgs::setup(argc,argv);
 
 // Check number of command line arguments: Need exactly three.
 if (argc!=4)
  {
   std::string error_message =
    "Wrong number of command line arguments.\n";
   error_message +=
    "Must specify the following file names  \n";
   error_message += 
    "filename.node then filename.ele then filename.face\n";
 
   throw OomphLibError(error_message,
                       OOMPH_CURRENT_FUNCTION,
                       OOMPH_EXCEPTION_LOCATION);
  }
 
 // Convert arguments to strings that specify the input file names
 string node_file_name(argv[1]);
 string element_file_name(argv[2]);
 string face_file_name(argv[3]);
 
 
 // Label for output
 DocInfo doc_info;
 
 // Output directory
 doc_info.set_directory("RESLT");
  
 // Number of output points per edge
 unsigned nplot=2;
 
 // Do the problem with linear elements
 //------------------------------------
 {
  PoissonProblem<TPoissonElement<3,2> > 
   problem(&TanhSolnForPoisson::get_source,
           node_file_name,element_file_name,face_file_name);
 
  // Solve the problem
  problem.newton_solve();
  
  //Output solution with 2 points per edge
  nplot=2;
  problem.doc_solution(nplot,doc_info);
    
  //Increment counter for solutions 
  doc_info.number()++;
 
  //Output solution with 5 points per edge
  nplot=5;
  problem.doc_solution(nplot,doc_info);
    
  //Increment counter for solutions 
  doc_info.number()++;
 
 
 }
 
 
 
 // Do the problem with quadratic elements
 //---------------------------------------
 {
  PoissonProblem<TPoissonElement<3,3> > 
   problem(&TanhSolnForPoisson::get_source,
           node_file_name,element_file_name,face_file_name);
  
  // Solve the problem
  problem.newton_solve();
 
  //Output solution with 2 points per edge
  nplot=2;
  problem.doc_solution(nplot,doc_info);
    
  //Increment counter for solutions 
  doc_info.number()++;
 
  //Output solution with 5 points per edge
  nplot=5;
  problem.doc_solution(nplot,doc_info);
    
  //Increment counter for solutions 
  doc_info.number()++;
 
 }
 
 
}

References TanhSolnForPoisson::get_source(), oomph::DocInfo::number(), OOMPH_CURRENT_FUNCTION, OOMPH_EXCEPTION_LOCATION, problem, oomph::DocInfo::set_directory(), Flag_definition::setup(), and oomph::Global_string_for_annotation::string().