问题
In my Graphviz graph (written in DOT), I want each node to have a label, but in addition to that, I want some nodes to have a small caption denoting some other unique value for that node. For example, if this were for a history diagram, a node's label might be something like "Birth of George Washington" and the caption might read "See also: American Revolution."
This is fairly flexible, so the caption doesn't necessarily need to be inside the node, but I do need some other way of putting text that clearly isn't part of the label (e.g. is a different size, possibly a different color) and is in a different location but is still clearly a part of the node.
Is there any way to do this?
回答1:
To place captions outside the node, you may use xlabel:
digraph g {
forcelabels=true;
a [label="Birth of George Washington", xlabel="See also: American Revolution"];
b [label="Main label", xlabel="Additional caption"];
a-> b;
}
forcelabels=true makes sure no xlabel is omitted.

A second option is to use HTML-like labels:
digraph g {
a[label=<Birth of George Washington<BR />
<FONT POINT-SIZE="10">See also: American Revolution</FONT>>];
}

来源:https://stackoverflow.com/questions/19280229/graphviz-putting-a-caption-on-a-node-in-addition-to-a-label