first example

.gitignore

@@ -9,3 +9,4 @@ compile_commands.json
 .ccls-cache/
 /iwyu/
 .Rhistory
+.vscode/

CMakeLists.txt

@@ -38,3 +38,5 @@ add_subdirectory(src)
 if(TUG_ENABLE_TESTING)
   add_subdirectory(test)
 endif()
+
+add_subdirectory(examples)

examples/CMakeLists.txt

@@ -0,0 +1,3 @@
+add_executable(first_example first_example.cpp)
+
+target_link_libraries(first_example tug)

examples/first_example.cpp

@@ -0,0 +1,67 @@
+#include "tug/BoundaryCondition.hpp"
+#include <tug/Diffusion.hpp>
+
+#include <iostream>
+#include <fstream>
+#include <string>
+
+using namespace std;
+using namespace tug::diffusion;
+using namespace tug::bc;
+
+int main(int argc, char *argv[]) {
+
+    // define problem dimensionality
+    // set grid sizes for each dimension
+    int dim = 1;
+    int n = 20;
+
+    vector<double> alpha(n, 1e-1);
+    // double alpha = 1e-1;
+    vector<double> field(n, 1e-6);
+    for (int i = 1; i<20; i++) {
+        field[i] = 0;
+    }
+    // double field = 1e-6;
+
+    
+    TugGrid grid_param; // why is grid_param defined separately?
+    // grid_param.grid_cells[0] = 20;
+    // grid_param.grid_cells[1] = 0;
+    // grid_param.grid_cells[2] = 0;
+
+    // grid_param.domain_size[0] = 20;
+    // grid_param.domain_size[1] = 0;
+    // grid_param.domain_size[2] = 0;
+
+    
+
+    TugInput input_param;
+    input_param.setTimestep(1.);
+    //input_param.grid = grid_param; 
+    input_param.setGridCellN(n);
+    input_param.setDomainSize(n); // what is domain?????
+    BoundaryCondition bc(n);
+    input_param.setBoundaryCondition(bc);
+
+    ofstream myfile;
+    myfile.open("output.csv"); 
+    if (!myfile) {
+        exit(1);
+    }
+
+    for (int t = 0; t < 10000; t++) {
+        double result = BTCS_1D(input_param, &field[0], &alpha[0]);
+        //myfile << result;
+        //myfile << '\n';
+        //myfile << "Vector contents: ";
+        for (int i = 0; i < field.size(); i++) {
+            myfile << field[i];
+            if (i < field.size()-1) {
+                myfile << ", ";
+            }
+        }
+        myfile << std::endl;
+    }
+    myfile.close();
+}