rbmatlab  1.16.09
 All Classes Namespaces Files Functions Variables Modules Pages
get_infsup.m
1 function infsup_beta = get_infsup(model,K,W)
2 %function cont_gamma = get_continuity(model,A,W)
3 %
4 % This function computes the inf-sup-constant beta for a discrete
5 % operator K with respect to the inner product matrix (mass matrix) W.
6 %
7 % A generalized eigenvalue problem is solved for obtaining the continuity
8 % constant beta.
9 %
10 % input:
11 % - K: Operator Matrix
12 % - W: inner product matrix
13 %
14 % output:
15 % - infsup_beta : continuity constant.
16 %
17 % This function does exactly the same as get_coercivity.m
18 % but returns the smallest eigenvalue.
19 %
20 % Oliver Zeeb
21 
22 Y=K'*(W\K);
23 infsup_beta = sqrt(eigs(Y,W,1,'sm'));