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AdjacencyGraph[{{1, 1, 0}, {0, 0, 1}, {0, 0, 1}}, 
 DirectedEdges -> True]

If you look very closely at the resulting visual display in a notebook (below), you can see narrowing where the arrow heads might be. Many adjacency graphs display without problem. What is causing this display problem? Is there a general but not complex approach (i.e., an approach suitable to real-time classroom display) to avoiding this problem? (Mma version 10.2 on Win 7.)

graph plot with missing arrows

Szabolcs
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Alan
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    There were questions about this before, but I cannot find them. Yes, this is very annoying. It happens because the arrowhead size is a fixed fraction of the image width. If the image is narrow, the arrowheads are small, sometimes literally invisible. Consider using the option EdgeStyle -> Arrowheads[Medium] which forces an absolute measurement independent of the image size. Related: http://mathematica.stackexchange.com/q/788/12 You can also consider complaining to Wolfram Support, maybe they'll give this more priority then ... – Szabolcs Oct 28 '15 at 15:47
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    Actually, looking more carefully, this is fixed in version 10.3. David's answer doesn't show it because that display of the graph is wide. But PathGraph[Range[3], DirectedEdges -> True, GraphLayout -> "LayeredDigraphEmbedding"] does. The arrowheads are invisible in 10.2 and look fine in 10.3 – Szabolcs Oct 28 '15 at 16:05

1 Answers1

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In Mathematica 10.3,

 AdjacencyGraph[{{1, 1, 0}, {0, 0, 1}, {0, 0, 1}}, 
 DirectedEdges -> True]

yields

enter image description here

David G. Stork
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    You are right: it did get fixed in 10.3. But this example does not show that. Please see my comments under the question. – Szabolcs Oct 28 '15 at 16:10
  • I'm accepting this answer because it meets my needs, but I understand @Szabolcs reservations and his suggestion to use EdgeStyle -> Arrowheads[Medium]. Thanks! – Alan Oct 28 '15 at 19:24