Source code for the tests in the paper A characterization of optimal two-phase multifunctional composite designs.

• A finite element code for the first test.
  This program computes the effective conductivity of various two phase composites using a finite element approximation of first order with a uniform grid. Then it computes the value of the solution to the cell problems at two points that are known to be on the interface. The code is well documented and the program is very talkative, so it shouldn't be hard to understand.
• An adaptive finite element code for the first test.
  This program computes the effective conductivity of a two phase composite using a finite element approximation of first order with an adaptive grid. Then it computes the value of the solution to the cell problems at two points that are known to be on the interface. We thank Luca Heltai for this code. The program requires the GPL library deal.II in order to compile.
• An finite difference code for the second test.
  This program computes a solution to the two phase problem where Laplacian u = -1 or 1 depending on whether u>0 or whether u<0. The computed function is periodic and cubically symmetric in the cube [-1,1]^3. Then the values of the normal derivative of u are computed at two points that are known to be on the free boundary.