ePiX is a LATEX pre-processor that creates mathematically accurate plots and
line figures using easy-to-learn syntax. The user interface is superficially
that of LATEX itself: You prepare a short input file and ``run ePiX'' on this
file, which produces a text file that is included into a LATEX document.
Because the output is plain text, the output can be edited manually if
necessary. However, for most visual tweaking it is easier and safer to change
the source and re-run ePiX.