Syntax:
set terminal gpic {<x> <y>}
where x and y are in inches.
A simple graph can be formatted using
groff -p -mpic -Tps file.pic > file.ps.
The output from pic can be pipe-lined into eqn, so it is possible to put complex functions in a graph with the set label and set {x/y}label commands. For instance,
set ylab '@space 0 int from 0 to x alpha ( t ) roman d t@'
will label the y axis with a nice integral if formatted with the command:
gpic filename.pic | geqn -d@@ -Tps | groff -m[macro-package] -Tps > filename.ps
Figures made this way can be scaled to fit into a document. The pic language is easy to understand, so the graphs can be edited by hand if need be. All co-ordinates in the pic-file produced by gnuplot are given as x+gnuplotx and y+gnuploty. By default x and y are given the value 0. If this line is removed with an editor in a number of files, one can put several graphs in one figure like this (default size is 5.0x3.0 inches):
.PS 8.0 x=0;y=3 copy "figa.pic" x=5;y=3 copy "figb.pic" x=0;y=0 copy "figc.pic" x=5;y=0 copy "figd.pic" .PE
This will produce an 8-inch-wide figure with four graphs in two rows on top of each other.
One can also achieve the same thing by specifying x and y in the command
set terminal gpic x y