diff --git a/src/BTCSDiffusion.cpp b/src/BTCSDiffusion.cpp
index af4c6f7..6a95b1c 100644
--- a/src/BTCSDiffusion.cpp
+++ b/src/BTCSDiffusion.cpp
@@ -22,23 +22,40 @@ BTCSDiffusion::BTCSDiffusion(unsigned int dim) : grid_dim(dim) {
   deltas.resize(dim, 1);
 }
 
-std::vector<int> BTCSDiffusion::getNumberOfGridCells() {
-  return this->grid_cells;
-}
-std::vector<int> BTCSDiffusion::getSpatialDiscretization() {
-  return this->domain_size;
-}
-void BTCSDiffusion::setNumberOfGridCells(std::vector<int> &n_grid) {
-  grid_cells = n_grid;
-  assert(grid_cells.size() == grid_dim);
+void BTCSDiffusion::setXDimensions(unsigned int domain_size,
+                                   unsigned int n_grid_cells) {
+  assert(this->grid_dim > 0);
+  this->domain_size[0] = domain_size;
+  this->grid_cells[0] = n_grid_cells;
+
   updateInternals();
 }
-void BTCSDiffusion::setSpatialDiscretization(std::vector<int> &s_grid) {
-  domain_size = s_grid;
-  assert(domain_size.size() == grid_dim);
+
+void BTCSDiffusion::setYDimensions(unsigned int domain_size,
+                                   unsigned int n_grid_cells) {
+  assert(this->grid_dim > 1);
+  this->domain_size[1] = domain_size;
+  this->grid_cells[1] = n_grid_cells;
+
   updateInternals();
 }
 
+void BTCSDiffusion::setZDimensions(unsigned int domain_size,
+                                   unsigned int n_grid_cells) {
+  assert(this->grid_dim > 2);
+  this->domain_size[2] = domain_size;
+  this->grid_cells[2] = n_grid_cells;
+
+  updateInternals();
+}
+
+unsigned int BTCSDiffusion::getXGridCellsN() { return this->grid_cells[0]; }
+unsigned int BTCSDiffusion::getYGridCellsN() { return this->grid_cells[1]; }
+unsigned int BTCSDiffusion::getZGridCellsN() { return this->grid_cells[2]; }
+unsigned int BTCSDiffusion::getXDomainSize() { return this->domain_size[0]; }
+unsigned int BTCSDiffusion::getYDomainSize() { return this->domain_size[1]; }
+unsigned int BTCSDiffusion::getZDomainSize() { return this->domain_size[2]; }
+
 void BTCSDiffusion::updateInternals() {
   for (int i = 0; i < grid_dim; i++) {
     deltas[i] = (double)domain_size[i] / grid_cells[i];
@@ -50,7 +67,7 @@ void BTCSDiffusion::updateInternals() {
     cells *= (grid_cells[i] + 2);
   }
 
-  bc.resize(cells, {BTCSDiffusion::BC_CLOSED,0});
+  bc.resize(cells, {BTCSDiffusion::BC_CLOSED, 0});
 }
 // BTCSDiffusion::BTCSDiffusion(int x) : n_x(x) {
 //   this->grid_dim = 1;
diff --git a/src/BTCSDiffusion.hpp b/src/BTCSDiffusion.hpp
index af08e0a..7954022 100644
--- a/src/BTCSDiffusion.hpp
+++ b/src/BTCSDiffusion.hpp
@@ -3,6 +3,7 @@
 
 #include <Eigen/Sparse>
 #include <tuple>
+#include <type_traits>
 #include <vector>
 
 /*!
@@ -70,11 +71,16 @@ public:
    */
   BTCSDiffusion(unsigned int dim);
 
-  std::vector<int> getNumberOfGridCells();
-  std::vector<int> getSpatialDiscretization();
-  void setNumberOfGridCells(std::vector<int> &n_grid);
-  void setSpatialDiscretization(std::vector<int> &s_grid);
+  void setXDimensions(unsigned int domain_size, unsigned int n_grid_cells);
+  void setYDimensions(unsigned int domain_size, unsigned int n_grid_cells);
+  void setZDimensions(unsigned int domain_size, unsigned int n_grid_cells);
 
+  unsigned int getXGridCellsN();
+  unsigned int getYGridCellsN();
+  unsigned int getZGridCellsN();
+  unsigned int getXDomainSize();
+  unsigned int getYDomainSize();
+  unsigned int getZDomainSize();
   // /*!
   //  * Currently not implemented: Create 2D-diffusion module.
   //  *
@@ -127,7 +133,8 @@ private:
   void simulate2D(std::vector<double> &c);
   void simulate3D(std::vector<double> &c);
 
-  inline double getBCFromFlux(boundary_condition bc, double nearest_value, double neighbor_alpha);
+  inline double getBCFromFlux(boundary_condition bc, double nearest_value,
+                              double neighbor_alpha);
 
   void updateInternals();
 
@@ -140,8 +147,8 @@ private:
   double time_step;
 
   int grid_dim;
-  std::vector<int> grid_cells;
-  std::vector<int> domain_size;
+  std::vector<unsigned int> grid_cells;
+  std::vector<unsigned int> domain_size;
   std::vector<double> deltas;
 };
 
diff --git a/src/main.cpp b/src/main.cpp
index c4549ee..cefb789 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -18,11 +18,7 @@ int main(int argc, char *argv[]) {
   // create instance of diffusion module
   BTCSDiffusion diffu(dim);
 
-  std::vector<int> vec_n = diffu.getNumberOfGridCells();
-
-  vec_n[0] = n;
-
-  diffu.setNumberOfGridCells(vec_n);
+  diffu.setXDimensions(1, n);
 
   // set the boundary condition for the left ghost cell to dirichlet
   diffu.setBoundaryCondition(0, 5. * std::pow(10, -6),