First you need to obtain the graph.tar.gz file either from
the web at https://www.ndsu.edu/pubweb/ carswagn/
or from another source and put it in your home directory.
Also make sure that you have installed the development libraries for the X11 system.
You then type
tar xzvf graph.tar.gz
cd c/graph
make install
If you don't get error messages this will successfully install the
library in your system.
