How to delete graph edges with specified weights?

Question

I wonder, if it's possible to delete graph edges on the base of their weights. In other words, can patterns in the function EdgeDelete[g,patt] include weights of edges to delete? WM Documentation doesn't describe these options.

Answer 1

You can use the pattern

_?(yourCondition @ PropertyValue[{g, #}, EdgeWeight] &)

or the pattern

e_ /; (yourCondition @ PropertyValue[{g, e}, EdgeWeight]

Examples:

g1 = CompleteGraph[4, EdgeWeight -> Range[6], 
  VertexLabels -> Automatic, EdgeLabels -> "EdgeWeight"]

g2 = EdgeDelete[g1, _?(OddQ @ PropertyValue[{g1, #}, EdgeWeight] &)];

(* or g2 = EdgeDelete[g1, e_ /; (OddQ @ PropertyValue[{g1, e}, EdgeWeight])]; *)

Graph[g2, VertexCoordinates -> GraphEmbedding[g1]]

forbiddenweights = {1, 3, 4};

g3 = EdgeDelete[g1, _?(MatchQ[Alternatives @@ forbiddenweights]@
      PropertyValue[{g1, #}, EdgeWeight] &)];

Graph[g3, VertexCoordinates -> GraphEmbedding[g1]]