Assembly of the Stiffness Matrix by $P_1$ -Lagrange finite elements in 3D. More...

Functions
function R =	StiffAssembling3DP1base (nq, nme, q, me, volumes)
	Assembly of the Stiffness Matrix by -Lagrange finite elements in 3D.

Detailed Description

Assembly of the Stiffness Matrix by $P_1$ -Lagrange finite elements in 3D.

Function Documentation

function R = StiffAssembling3DP1base	(	nq,
		nme,
		q,
		me,
		volumes
	)

Assembly of the Stiffness Matrix by $P_1$ -Lagrange finite elements in 3D.

The Stiffness Matrix $\Stiff$ is given by

$\Stiff_{i,j}=\int_\DOMH \DOT{\GRAD\FoncBase_i(\q)}{\GRAD\FoncBase_j(\q)}d\q,\ \forall (i,j)\in{\ENS{1}{\nq}}^2$

where $\FoncBase_i$ are $P_1$ -Lagrange basis functions.

Example

    Th=CubeMesh(10);
    R=StiffAssembling3DP1base(Th.nq,Th.nme,Th.q,Th.me,Th.volumes);

Parameters

nq	total number of vertices, also denoted by $\nq$ .
nme	total number of elements, also denoted by $\nme$ .
q	Array of vertices coordinates, $3\times\nq$ array. ${\q}(\il,j)$ is the $\il$ -th coordinate of the -th vertex, $\il\in\{1,2,3\}$ and $j\in\ENS{1}{\nq}$
me	Connectivity array, $4\times\nme$ array. $\me(\jl,k)$ is the storage index of the $\jl$ -th vertex of the -th tetrahedron in the array $\q$ of vertices coordinates, $\jl\in\{1,2,3,4\}$ and $k\in{\ENS{1}{\nme}}$ .
volumes	Array of volumes, $1\times\nme array$ . volumes(k) is the volume of the k-th tetrahedron.

Return values

R	Global stiffness matrix, $\nq\times\nq$ sparse matrix.

Definition at line 17 of file StiffAssembling3DP1base.m.