first draft (FEM only)

tutorials/poisson_overlap/CMakeLists.txt

+cmake_minimum_required(VERSION 3.0 FATAL_ERROR)
+
+project(tuto CXX)
+
+include(${CMAKE_CURRENT_SOURCE_DIR}/../tutorial.cmake)
+
+add_executable(tuto main.cpp ${EXTRA_INCS})
+target_link_libraries(tuto ${EXTRA_LIBS})

tutorials/poisson_overlap/domain.geo

+// Gmsh project created on Thu Oct  6 12:29:07 2022
+//SetFactory("OpenCASCADE");
+//+
+Point(1) = {0, 0, 0, 0.05};
+//+
+Point(2) = {0.8, 0, 0, 0.05};
+//+
+Point(3) = {1.2, 0, 0, 0.05};
+//+
+Point(4) = {2.0, 0, 0, 0.05};
+//+
+Point(5) = {2, 1, 0, 0.05};
+//+
+Point(6) = {1.2, 1, 0, 0.05};
+//+
+Point(7) = {0.8, 1, 0, 0.05};
+//+
+Point(8) = {0.0, 1, 0, 0.05};
+//+
+Line(1) = {1, 2};
+//+
+Line(2) = {2, 7};
+//+
+Line(3) = {7, 8};
+//+
+Line(4) = {8, 1};
+//+
+Line(5) = {3, 2};
+//+
+Line(6) = {6, 3};
+//+
+Line(7) = {6, 7};
+//+
+Line(8) = {3, 4};
+//+
+Line(9) = {4, 5};
+//+
+Line(10) = {5, 6};
+//+
+Curve Loop(1) = {4, 1, 2, 3};
+//+
+Plane Surface(1) = {1};
+//+
+Curve Loop(2) = {7, -2, -5, -6};
+//+
+Plane Surface(2) = {2};
+//+
+Curve Loop(3) = {10, 6, 8, 9};
+//+
+Plane Surface(3) = {3};
+//+
+Physical Surface("left", 11) = {1};
+//+
+Physical Surface("center", 12) = {2};
+//+
+Physical Surface("right", 13) = {3};
+//+
+Physical Curve("gammaLeft", 14) = {4};
+//+
+Physical Curve("gammaRight", 15) = {9};
+//+
+Physical Curve("interface1", 16) = {2};
+//+
+Physical Curve("interface2", 17) = {6};

tutorials/poisson_overlap/main.cpp

+#include "gmsh.h"
+
+#include <gmshddm/Formulation.h>
+#include <gmshddm/GmshDdm.h>
+#include <gmshddm/MPIInterface.h>
+#include <gmshfem/Message.h>
+#include <gmshfem/GmshFem.h>
+#include <gmshfem/Formulation.h>
+
+
+using namespace gmshfem;
+using namespace gmshfem::common;
+using namespace gmshfem::problem;
+using namespace gmshfem::domain;
+using namespace gmshfem::field;
+using namespace gmshfem::function;
+using namespace gmshfem::post;
+using namespace gmshfem::equation;
+
+
+/*  
+using namespace gmshddm;
+using namespace gmshddm::common;
+using namespace gmshddm::domain;
+using namespace gmshddm::problem;
+using namespace gmshddm::field;
+using namespace gmshddm::mpi;
+*/
+
+
+int main(int argc, char **argv)
+{
+  //GmshDdm gmshDdm(argc, argv);
+  GmshFem gmshFem(argc, argv);
+
+  unsigned int nDom = 2;
+  gmshFem.userDefinedParameter(nDom, "nDom");
+
+  double lc = 0.05;
+
+  int order = 1;
+  
+  gmshFem.userDefinedParameter(lc, "lc");
+  gmshFem.userDefinedParameter(order, "order");
+  std::string gauss = "Gauss10";
+  gmshFem.userDefinedParameter(gauss, "gauss");
+
+  gmsh::open("../domain.geo");
+  gmsh::model::mesh::generate();
+
+  Formulation< std::complex< double > > formulation("demoFloatingPotential");
+
+  Domain left(2, 11), center(2, 12), right(2, 13);
+  Domain gammaLeft(1, 14), interface1(1, 16), interface2(1, 17), gammaRight(1, 15);
+
+  Field<std::complex<double>, Form::Form0> v("v", left|center|interface2|interface1, FunctionSpaceTypeForm0::Lagrange);
+  v.addConstraint(interface2, 0);
+
+  formulation.integral(grad(dof(v)), grad(tf(v)), left|center|interface2|interface1, gauss);
+  formulation.integral(-1.0, tf(v), gammaLeft, gauss);
+  
+  formulation.pre();
+  formulation.assemble();
+  formulation.solve();
+
+  save(v);
+
+  return 0;
+}