graphstruct.C File Reference

Detailed Description

Draw a simple graph structure.

The graph layout is made using graphviz. This macro creates some nodes and edges and change a few graphical attributes on some of them.

 
TCanvas *graphstruct()
{
#if __has_include("TGraphStruct.h") // handy check on whether gviz was installed
   TGraphStruct *gs = new TGraphStruct();
 
   // create some nodes and put them in the graph in one go ...
   TGraphNode *n0 = gs->AddNode("n0", "Node 0");
   TGraphNode *n1 = gs->AddNode("n1", "First node");
   TGraphNode *n2 = gs->AddNode("n2", "Second node");
   TGraphNode *n3 = gs->AddNode("n3", "Third node");
   TGraphNode *n4 = gs->AddNode("n4", "Fourth node");
   TGraphNode *n5 = gs->AddNode("n5", "5th node");
   TGraphNode *n6 = gs->AddNode("n6", "Node number six");
   TGraphNode *n7 = gs->AddNode("n7", "Node 7");
   TGraphNode *n8 = gs->AddNode("n8", "Node 8");
   TGraphNode *n9 = gs->AddNode("n9", "Node 9");
 
   n4->SetTextSize(0.03);
   n6->SetTextSize(0.03);
   n2->SetTextSize(0.04);
 
   n3->SetTextFont(132);
 
   n0->SetTextColor(kRed);
 
   n9->SetFillColor(kRed - 10);
   n0->SetFillColor(kYellow - 9);
   n7->SetFillColor(kViolet - 9);
 
   // some edges ...
   gs->AddEdge(n0, n1)->SetLineColor(kRed);
   TGraphEdge *e06 = gs->AddEdge(n0, n6);
   e06->SetLineColor(kRed - 3);
   e06->SetLineWidth(4);
   gs->AddEdge(n1, n7);
   gs->AddEdge(n4, n6);
   gs->AddEdge(n3, n9);
   gs->AddEdge(n6, n8);
   gs->AddEdge(n7, n2);
   gs->AddEdge(n8, n3);
   gs->AddEdge(n2, n3);
   gs->AddEdge(n9, n0);
   gs->AddEdge(n1, n4);
   gs->AddEdge(n1, n6);
   gs->AddEdge(n2, n5);
   gs->AddEdge(n3, n6);
   gs->AddEdge(n4, n5);
 
   TCanvas *c = new TCanvas("c", "c", 800, 600);
   c->SetFillColor(38);
   gs->Draw();
   return c;
#else
   return new TCanvas("c", "c", 800, 600);
#endif
}

Note

For this to work, ROOT has to be compiled with gviz ON

Author

Olivier Couet

Definition in file graphstruct.C.