message: Add static variables to manage the mesh size for cartesian example
diff: using namespace axom;
  using namespace sidre;
  +static int cart_nx = 5; // nodal domain x size for cartesian mesh example
  +static int cart_ny = 5; // nodal domain y size for cartesian mesh example
  +
  DataStore* create_tiny_datastore()
  {
  DataStore* ds = new DataStore();
  @@ -113,21 +116,17 @@ void setup_blueprint_coords(DataStore* ds, Group* coords)
  void setup_cartesian_coords(Group* coords, int domain_id)
  {
  - // 5x5 vertices, 4x4 elements
  - int nx = 5;
  - int ny = 5;
  -
  // Set up uniform cartesian coordinates
  coords->createViewString("type", "uniform");
  - coords->createViewScalar("dims/i", nx);
  - coords->createViewScalar("dims/j", ny);
  + coords->createViewScalar("dims/i", cart_nx);
  + coords->createViewScalar("dims/j", cart_ny);
  double x_lo = static_cast<double>(domain_id);
  double x_hi = x_lo + 1.0;
  - double dx = (x_hi - x_lo) / static_cast<double>(nx - 1);
  + double dx = (x_hi - x_lo) / static_cast<double>(cart_nx - 1);
  double y_lo = 0.0;
  double y_hi = 1.5;
  - double dy = (y_hi - y_lo) / static_cast<double>(ny - 1);
  + double dy = (y_hi - y_lo) / static_cast<double>(cart_ny - 1);
  coords->createViewScalar("origin/x", x_lo);
  coords->createViewScalar("origin/y", y_lo);
  coords->createViewScalar("spacing/dx", dx);
  @@ -183,12 +182,11 @@ void setup_blueprint_topos(DataStore* ds, Group* topos)
  void setup_cartesian_topos(Group* topos)
  {
  - //Set up topology using prior knowledge of nx and ny values from coords
  Group* structmesh = topos->createGroup("cartesian");
  structmesh->createViewString("type", "structured");
  structmesh->createViewString("coordset", "coords");
  - structmesh->createViewScalar("elements/dims/i", 4); // must match nx-1
  - structmesh->createViewScalar("elements/dims/j", 4); // must match ny-1
  + structmesh->createViewScalar("elements/dims/i", cart_nx-1);
  + structmesh->createViewScalar("elements/dims/j", cart_ny-1);
  }
  void setup_blueprint_fields(DataStore* ds, Group* fields)
  @@ -221,12 +219,10 @@ void setup_blueprint_fields(DataStore* ds, Group* fields)
  void setup_cartesian_fields(Group* fields)
  {
  // Match known values from setup_cartesian_coords
  - int nx = 5;
  - int ny = 5;
  - int ex = nx - 1;
  - int ey = ny - 1;
  + int ex = cart_nx - 1;
  + int ey = cart_ny - 1;
  int eltcount = ex * ey;
  - int nodecount = nx * ny;
  + int nodecount = cart_nx * cart_ny;
  // Create a node-centered field and an element-centered field
  Group* nodefield = fields->createGroup("nodefield");
  @@ -238,11 +234,11 @@ void setup_cartesian_fields(Group* fields)
  double* nptr = nodes->getArray();
  - for(int j = 0; j < ny; ++j)
  + for(int j = 0; j < cart_ny; ++j)
  {
  - for(int i = 0; i < nx; ++i)
  + for(int i = 0; i < cart_nx; ++i)
  {
  - nptr[j * nx + i] = static_cast<double>(i * j);
  + nptr[j * cart_nx + i] = static_cast<double>(i * j);
  }
  }
  