void FruchtermanReingold :: calculate_exact_repulsive_forces(const Graph &G, NodeArray
<NodeAttributes> &A, NodeArray<DPoint>& F_rep)
{
//naive algorithm by Fruchterman & Reingold
mathExtension M;
numexcept N;
node v,u;
DPoint f_rep_u_on_v;
DPoint vector_v_minus_u;
DPoint pos_u,pos_v;
DPoint nullpoint (0,0);
double norm_v_minus_u;
long node_number = G.numberOfNodes();
Array<node> array_of_the_nodes (node_number+1);
long counter = 1;
long i,j;
double scalar;
forall_nodes(v,G)
F_rep[v]= nullpoint;
forall_nodes(v,G)
{
array_of_the_nodes[counter]=v;
counter++;
}
void FruchtermanReingold::calculate_exact_repulsive_forces(
const Graph &G,
NodeArray<NodeAttributes> &A,
NodeArray<DPoint>& F_rep)
{
//naive algorithm by Fruchterman & Reingold
numexcept N;
DPoint f_rep_u_on_v;
DPoint vector_v_minus_u;
DPoint pos_u, pos_v;
DPoint nullpoint(0, 0);
double norm_v_minus_u;
int node_number = G.numberOfNodes();
Array<node> array_of_the_nodes(node_number + 1);
double scalar;
for (node v : G.nodes)
F_rep[v] = nullpoint;
int counter = 1;
for (node v : G.nodes)
{
array_of_the_nodes[counter] = v;
counter++;
}
for (int i = 1; i < node_number; i++) {
for (int j = i + 1; j <= node_number; j++)
{
node u = array_of_the_nodes[i];
node v = array_of_the_nodes[j];
pos_u = A[u].get_position();
pos_v = A[v].get_position();
if (pos_u == pos_v)
{//if2 (Exception handling if two nodes have the same position)
pos_u = N.choose_distinct_random_point_in_radius_epsilon(pos_u);
}//if2
vector_v_minus_u = pos_v - pos_u;
norm_v_minus_u = vector_v_minus_u.norm();
if (!N.f_rep_near_machine_precision(norm_v_minus_u, f_rep_u_on_v))
{
scalar = f_rep_scalar(norm_v_minus_u) / norm_v_minus_u;
f_rep_u_on_v.m_x = scalar * vector_v_minus_u.m_x;
f_rep_u_on_v.m_y = scalar * vector_v_minus_u.m_y;
}
F_rep[v] = F_rep[v] + f_rep_u_on_v;
F_rep[u] = F_rep[u] - f_rep_u_on_v;
}
}
}
