idiscretization.c File Reference

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Detailed Description

The code in this file assembles the local finite element matrix and inserts it into the global finite element matrices.

Copyright by Benedikt Oswald, 2002-2006, all rights reserved.

Objective: compute local, aka elemental, finite elemental matrices and insert it into the global finite elemental matrix.

Details: this code represents the very connection between the PDE and its discretized formulation based on the the Galerkin approach. The discretization is based on material from the paper in J. F. Lee, IEEE Microwave and Guided Wave Letters, Vol. 4(1), January, 1994, pp. 11-13.

Author:

Benedikt Oswald

Date:

2003 jun 11 ~ 11:26:00 by benedikt oswald - structure from ediscretization.c

2003 jun 11 ~ 00:00:00 by benedikt oswald

Warning:

none

Attention:

none required

Bug:

this is a research code.

Todo:

#include <math.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "gm.h"
#include "ugstruct.h"
#include "misc.h"
#include "ugdevices.h"
#include "commands.h"
#include "cmdint.h"
#include "cmdline.h"
#include "general.h"
#include "np.h"
#include "assemble.h"
#include "quadrature.h"
#include "shapes.h"
#include "idiscretization.h"

Functions
INT	AssembleTetrahedronPEC (NP_BASE *base, ELEMENT *t, INT argc, char **argv)

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Function Documentation

INT AssembleTetrahedronPEC	(	NP_BASE *	base,
		ELEMENT *	t,
		INT	argc,
		char **	argv
	)

AssembleTetrahedronPEC - compute local matrices and accumulate them

SYNOPSIS: static int AssembleTetrahedronPEC(...)

PARAMETERS:

DESCRIPTION:

This function constructs the elemental matrices, namely:

[T_ij] e_tt + [R_ij] e_t + [S_ij] e + F_i = 0

/ where [T_ij] = epsilon | w1_i * w1_j dV /

/ where [R_ij] = sigma | w1_i * w1_j dV /

/ where [S_ij] = (1/mu) | ( Nabla x w1_i ) * ( Nabla x w1_j ) dV /

/ where [F_i] = | w1_i ) * d/dt J_0 dV /

with J_0 defined as the impressed or forced current with [T_ij] and [R_ij] being scaled versions of the same integral expression

SEE ALSO: diff2d, assemble

RETURN VALUE: INT

FE_OK if ok FE_NOT_TETRAHEDRON if not tetrahedron FE_BAD_TRAFO if bad trafo FE_NO_CONNECTION if no connection

construct elemental matrices [T_ij] and [R_ij], therefore double loop over the edges (ei,ej) of the current tetrahedron; carry out Gaussian quadrature within the doubly nested loop forevery combination of the edges of a tetrahedron; there is some optimization potential because the matrix is symmetrix and it has not yet been exploited.

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