Two-phase obstacle problem in 2D and its aposteriori error estimate

Calculation of two-phase obstacle problem in 2D and its a posteriori error estimate

This code computes a finite element (FEM) approximation to two benchmark two-phase obstacle problems in 2D. The FEM approximation is constructed from the maximization of the Lagrange multiplier in a dual problem. It leads to a quadratic programming problem with box constrains. Therefore, the optimization toolbox of MATLAB is required to run the code. Once the approximation is available, its quality is measured in terms of a posteriori error estimate.
Details on theory and numerics will be found in the forthcoming paper of Farid Borzorgnia and Jan Valdman: A FEM approximation of a two-phase obstacle problem and its a posteriori error estimate (submitted).
A link to the paper will be found at the author's web page http://sites.google.com/site/janvaldman/publications .
Please cite the paper if you find the code useful.

Call 'start' in the 'solver_two_phase_obstacle' directory to run the code.