solved all left magic numbers

Author: salva24

src/cart_tumor.cc

@@ -48,8 +48,8 @@ int Simulate(int argc, const char** argv) {
     // Periodic boundary conditions
     param->bound_space = Param::BoundSpaceMode::kTorus;
     // Cube of kBoundedSpaceLength³ centered at origin
-    param->min_bound = -kBoundedSpaceLength / 2.0;
-    param->max_bound = kBoundedSpaceLength / 2.0;
+    param->min_bound = -kBoundedSpaceLength / kHalf;
+    param->max_bound = kBoundedSpaceLength / kHalf;
     param->simulation_time_step = kDt;
   };
 

src/diffusion_thomas_algorithm.cc

@@ -50,7 +50,7 @@ DiffusionThomasAlgorithm::DiffusionThomasAlgorithm(int substance_id,
       jump_k_(resolution_ * resolution_),
       spatial_diffusion_coeff_(dc * dt / (d_space_ * d_space_)),
       neg_diffusion_factor_(-spatial_diffusion_coeff_),
-      temporal_decay_coeff_(mu * dt / 3.0),
+      temporal_decay_coeff_(mu * dt / kThird),
       central_coeff_(1.0 + 2 * spatial_diffusion_coeff_ +
                      temporal_decay_coeff_),
       edge_coeff_(1.0 + spatial_diffusion_coeff_ + temporal_decay_coeff_),

src/hyperparams.h

@@ -141,6 +141,8 @@ constexpr real_t kReductionConsumptionDeadCells = 0.1;
 
 /// Constant for division by 2.0
 constexpr real_t kHalf = 2.0;
+/// Constant for division by 3.0
+constexpr real_t kThird = 3.0;
 
 /// Chemicals
 ///  Number of voxels per axis for the substances grid