COMSOL Multiphysics™

elinv
Purpose
elinv
Define matrix inverse component variables.
Syntax
Description
el.elem = 'elinv'
el.g{ig} = geomnum
el.matrixdim = mdim
el.format = 'symmetric' | 'hermitian' | 'unsymmetric'
el.basename = bname
el.postname = pname
el.geomdim{ig}{edim}.ind{eldomgrp} = domainlist
el.geomdim{ig}{edim}.matrix{eldomgrp} = matexpr
The elinv element defines components of the inverse of an mdim-by-mdim matrix
field. The matexpr is a cell array of expressions which specify the source matrix in
column order. If the format is 'symmetric' or 'hermitian', only the upper
triangle has to be given.
Matrix inverse component names, that is, the variable names defined by the element,
are created by appending row and column indices to the bname parameter and, if
the postname field is present, append '_pname'. If the format is specified as
'symmetric', variables are generated only for the upper triangular part of the
inverse, otherwise for all components.
Examples
Define variables to evaluate the Jacobian inverse components for an explicit variable
transformation [X(x,y,z), Y(x,y,z), Z(x,y,z)].
el.elem = 'elconst';
el.var = {'X','2*x','Y','y+z','Z','z'};
fem.elem = [fem.elem {el}];
clear el;
el.elem = 'elinv';
el.g = {'1'};
el.matrixdim = '3';
el.format = 'unsymmetric';
el.basename = 'd';
gd.ind = {{'1'}};
gd.matrix = {{'diff(X,x)','diff(X,y)','diff(X,z)',...
'diff(Y,x)','diff(Y,y)','diff(Y,z)',...
'diff(Z,x)','diff(Z,y)','diff(Z,z)'}};
el.geomdim{1} = {{},{},gd};
fem.elem = [fem.elem {el}];
See Also
elempty, elpric
86 | CHAPTER 1: COMMAND REFERENCE