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Draw a Graph I (exer-graph)

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Problem

Define the undirected graph in Figure 1 and draw it with the drawing tool of LPL.


PIC

Figure 1: A Graph with 5 nodes and 8 edges


Solution

Listing 1: The Complete Model implemented in LPL [2]

model aGraph "Draw a Graph I"; 
  set i,j         "A set of nodes"; 
    e{i,j}        "A set of edges"; 
  parameter X{i}  "X-position of node"; 
            Y{i}  "Y-position of node";; 
  i :=[ a b c d e ]; 
  X{i} := [0 0 2 2 3]; 
  Y{i} := [0 2 0 2 1]; 
  e{i,j}:=[ (a,*) b c d, 
            (b,*) a c d, 
            (c,*) a b d e, 
            (d,*) a b c e, 
            (e,*) c d ]; 
  drawgraph; 
  -------------------- 
  model drawgraph; 
    Draw.Scale(60,60); 
    Draw.DefFont('Verdana',16); 
    {e[i,j]|i<j} Draw.Line(X[i],Y[i],X[j],Y[j]); 
    {i}Draw.Circle(i&'', X,Y,.2,1,0); 
  end 
end

References

[1]   MatMod. Homepage for Learning Mathematical Modeling :  https://matmod.ch.

[2]   Hürlimann T. Reference Manual for the LPL Modeling Language, most recent version. https://matmod.ch/lpl/doc/manual.pdf.