copied the templates

mgrid_2/generateCRS.cpp

@@ -0,0 +1,65 @@
+#include "binaryIO.h"
+#include "geom.h"
+#include "getmatrix.h"
+#include "jacsolve.h"
+#include "userset.h"
+#include "vdop.h"
+
+#include <cassert>
+#include <chrono>           // timing
+#include <cmath>
+#include <iostream>
+#include <string>
+#include <omp.h>
+#include <vector>
+using namespace std;
+using namespace std::chrono;  // timing
+
+///  Generates sparse matrices (CRS) and right hand side for the Laplace on the given mesh
+///  and stores them in binary files.
+///
+///  - meshname("square_100")   reads ASCii mesh file square_100.txt
+///  - Right hand side is defined via function fNice(x,y) in userset.h
+///  - the initial mesh is refined (nmesh-1) 2 times by standard.
+///  - ./generateCRS nmesh           --> nmesh-1 refinement steps
+
+int main(int argc, char **argv )
+{
+	const string meshname("square_100");
+	//const string meshname("square_06");
+    int nmesh = 3;
+    if (argc > 1)  nmesh = atoi(argv[1]);
+
+    Mesh const mesh_c(meshname+".txt");
+    bool ba = mesh_c.checkObtuseAngles();
+    if (ba) cout << "mesh corrected" << endl;
+    //mesh_c.Debug(); cout << endl << "#############################\n";
+
+    gMesh_Hierarchy ggm(mesh_c, nmesh);
+
+    for (size_t ll = 0; ll < ggm.size(); ++ll)
+    {
+        const Mesh &mesh = ggm[ll];
+		cout << "Matrix for mesh " << ll << " with " << mesh.Nnodes() << " nodes."<< endl;
+        FEM_Matrix SK(mesh);
+        vector<double> uv(SK.Nrows(), 0.0);    // temperature
+        vector<double> fv(SK.Nrows(), 0.0);    // r.h.s.
+        SK.CalculateLaplace(fv);
+        //SK.CheckRowSum();
+        SK.CheckMatrix();
+        mesh.SetValues(uv, [](double x, double y) -> double
+        {
+            return x *x * std::sin(2.5 * M_PI * y);
+        } );
+        SK.ApplyDirichletBC(uv, fv);
+
+        const string binname(meshname+"_"+to_string(ll)+"_mat"+".bin");
+        SK.writeBinary(binname);
+        const string rhsname(meshname+"_"+to_string(ll)+"_rhs"+".bin");
+        write_binVector(rhsname,fv);
+        //SK.Debug();
+    }
+
+    return 0;
+}
+