Added Dijkstra version for digraph with edges weights #319
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| @@ -1365,6 +1365,37 @@ InstallMethod(DigraphDijkstra, "for a digraph, and a vertex", | |||
| [IsDigraph, IsPosInt], | |||
| {digraph, source} -> DIGRAPHS_DijkstraST(digraph, source, fail)); | |||
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| InstallMethod(DigraphDijkstraSTWeights, "for a digraph, a vertex, a vertex, and a list of weights", | |||
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I suggest using your new version DigraphDijkstraSTWeights as the code of DIGRAPHS_DijkstraST, with one change: the argument weights could be a function like:
weights := function(u, v)
return list_of_weights[u][v];
end;
if a list of weights is given, and if no list of weights is given then we could do:
weights := function(u, v)
return 1;
end;
| u := Pop(queue); | ||
| u := u[2]; | ||
| for v in OutNeighbours(digraph)[u] do | ||
| alt := dist[u] + weights[u][v]; |
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would become weights(u, v) instead of weights[u][v]
| @@ -1365,6 +1365,37 @@ InstallMethod(DigraphDijkstra, "for a digraph, and a vertex", | |||
| [IsDigraph, IsPosInt], | |||
| {digraph, source} -> DIGRAPHS_DijkstraST(digraph, source, fail)); | |||
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{digraph, source} -> DIGRAPHS_DijkstraST(digraph, source, fail))
would become
{digraph, source} -> DIGRAPHS_DijkstraST(digraph, source, fail, {u, v} -> 1))
| InstallMethod(DigraphDijkstraSTWeights, "for a digraph, a vertex, a vertex, and a list of weights", | ||
| [IsDigraph, IsPosInt, IsPosInt, IsList], | ||
| function(digraph, source, target, weights) | ||
| local dist, prev, queue, u, v, alt; |
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Check that the weights have the same "shape" as OutNeighbours(digraph)
james-d-mitchell
requested changes
May 13, 2020
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