Visualizing Directed Edges in Graphs: Don't Use Arrows
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Visualizing Directed Edges in Graphs: Don't Use Arrows
1–10 of 17 posts
Re: Visualizing Directed Edges in Graphs: Don't Use Arrows
#2It's only better if you -- by reading up on convention beforehand -- know which way an edge points; does decreasing thickness indicate an incident node, or the opposite? Not clear on its own.
Re: Visualizing Directed Edges in Graphs: Don't Use Arrows
#3I really like the gradient use on the edges. That, along with the taper, allows a reader to easily see the direction without having to follow it till it hits another node.
Re: Visualizing Directed Edges in Graphs: Don't Use Arrows
#4Interesting, I feel for "trained" users who use directed graphs for work this is a valuable technique. But even the researchers admitted it is not obvious which way the flow goes. So I don't think it would work well for advertising or public presentations.
The research paper makes interesting reading, and how often can you say that!
Re: Visualizing Directed Edges in Graphs: Don't Use Arrows
#5While I understand how arrows on the end of the edge is a bad idea, especially if you have a lot of edges on one node; what about having arrows blended in the edge itself?
Something like this (beware the ASCII art): o---->----o
Re: Visualizing Directed Edges in Graphs: Don't Use Arrows
#6Umm... that's great for printed materials but how are you going to make that work on a white(black)board or for that matter with a pencil?
Not sure I've done many directed graphs in print but I've done quite a few with a marker/pencil/chalk.
Re: Visualizing Directed Edges in Graphs: Don't Use Arrows
#7It's only better if you -- by reading up on convention beforehand -- know which way an edge points; does decreasing thickness indicate an incident node, or the opposite? Not clear on its own.
It's an arrowhead. It goes in the direction it points.
For example, (A -> B) is drawn:
A @===---- BRe: Visualizing Directed Edges in Graphs: Don't Use Arrows
#8[deleted]
Re: Visualizing Directed Edges in Graphs: Don't Use Arrows
#9It's only better if you -- by reading up on convention beforehand -- know which way an edge points; does decreasing thickness indicate an incident node, or the opposite? Not clear on its own.
Agreed; my initial interpretation was thinking of the tapered edges as comet tails or motion blur, which is the opposite direction to what they want to depict.
Re: Visualizing Directed Edges in Graphs: Don't Use Arrows
#10While I understand how arrows on the end of the edge is a bad idea, especially if you have a lot of edges on one node; what about having arrows blended in the edge itself? Something like this (beware the ASCII art): o---->----o
I often do this in hand-drawn graphs for my own consumption, when the line is very long (sometimes using three arrowheads): o-->---------->----------->o
BTW: paper mentions the problem of visual clutter of the arrowhead itself.