I am currently using the latest version of Fenics on ubuntu. When trying to create subdomains using the MeshFunction, I get an error message stating that the function cannot be found. Keep in mind that that i already import dolfin in the start of the program. Is there an updated function to create subdomains in the latest version.
You may want to take a look at the subdomains demo which can be found here. In the case you cannot get it to work, feel free to post a minimal working example.