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3 problems with graph package in MuPAD

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I am a master student of operations research and must implement a 
heuristic algorithm of solving hazardous material transportation. 
I have uploaded a zipped file contains two documents describe model 
and algorithm. 
link of file: 
http://www.mediafire.com/download/5r35wgya0klanbd/scans.zip 
In order to implement this algorithm to random networks, i did steps below: 
1. generate random graph: 
G := Graph::createRandomGraph(n,m): 
2. assign random risks to edges in [a,,b]: 
G1 := Graph::createRandomEdgeCosts(G, a..b): 
3.solve minimum risk problems from node s to node d: 
G2:=Graph::shortestPathSingleSource(G1, StartVertex = [s], EndVertex = 
[d], SearchFor = Costs) 
-------first issue is that Graph::shortestPathSingleSource(G1, 
StartVertex = [1], SearchFor = Costs) don't get us the shortest path 
and only give value of shortest path value! (G1 is defined as 10th 
line in this text) 
------in step2, we must create a subgraph of G1 that contains specified 
edges (edges belong to shortest paths in step 1),how can i do this? 
but i can't create this sub graph because i only found 
Graph::getSubGraph(G, Vertex) returns a subgraph according to the 
specified vertex but we want that the subgraph contasins specified 
edges (edges belong to shortest paths in step 1) 
other problem is: 
------after solving minimum cost problems in step 2, we must remove edge 
with maximum risk from subgraph, but i don't know how to identify such 
edge (i can't find any functions identify edge with maximum edge 
weight in the graph) 
please help me 

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3 problems with graph package in MuPAD researcher2014 <m.ershadmanesh@gmail.com> - 2014-07-10 20:06 -0700

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