When putting together results, it's often desirable to have some professional looking diagrams, rather than diagrams put together in MS Paint. What is the standard for drawing data structures?
The MO thread Per links to is pretty good, and this thread on tex.SE is also handy. The main tools that I've used:
I know that Mac folks swear by Omnigraffle, but I have zero experience with it myself. The main criteria for me are:
- Generating PDF
- Integrating LaTeX (with source styles for bonus points)
- Being able to do color/shading etc easily. (Ipe 7 fails on that count)
Suresh recommended "Tikz/PGF" for LaTeX. In addition, for drawing graphs and the like, I recommend the following packages:
For a sample usage, see the gallery of named graphs.
See also other pages on http://www.altermundus.fr. (They are mostly in French, yet you can figure out the meaning using Google Translator.)
Suresh mentions OmniGraffle and Ross mentions Graphviz.
Actually, OmniGraffle is Graphviz with a GUI (and much more). You can draw a graph (or import it from a file), then use a Graphiz-based layout engine to automatically layout the graph. You can tweak the parameters of the layout engine, and finally you can switch off automatic layout and fine-tune the placement of the nodes manually.
That said, I still tend to use Xfig for most illustrations in my papers... The possibility to embed arbitrary Latex code in your illustrations is often essential, and that's exactly where Xfig excels (at least until you need to deal with publishers who expect self-contained EPS files).
Since some have mentioned Graphviz, there is also dot2tex which converts Graphviz code into TikZ. This makes using it within LaTeX (have mathematical expressions in labels etc.) and fine-tuning the appearance of the graph easier. You can even embed the Graphviz code directly in the TeX code (in a dot2tex environment) and have it run Graphviz automatically.
For simple drawings I prefer yEd. It can be launched straight from the browser.
Apart from TikZ and graphviz I have made good use of my graphics tablet. You can get the new small Wacom Bamboo for 50€ (used) to 100€ (new). With a tablet you can create quite good looking images quickly; for anything but journal/conference/book publications -- depending on your skill, even then -- the results are very presentable.
You might take a look at GePhi.