Version 2.0.  November 1990.

This package contains directories lib.d, automata.d and isom.d.
There are two collections of programs, of which the executables go into
automata.d/bin  and  isom.d/bin. Both of these directories should be put
into your path. Before making the isom package, you will probably need to
edit a directory name in isom.d/src/makefile, which is defined under the
entry for permim.o.

To make the packages, do the following:

cd lib.d  
make
cd ../automata.d/src
make all
cd ../../isom.d/src
make all

All of the individual programs have manual entries (in troff format) in
automata.d/man/man1 and isom.d/man/man1. The principal programs in the
two sections are automata and testisom, respectively. However, automata
has an alternative version called automatac which performs better on some
examples.

automata (which is a Bourne shell script, which runs the other programs)
takes as input a finitely presented group, and attempts to construct the
finite state automata associated with a lex-least automatic structure of the
group. If successful, the word acceptor automaton will end up in the file
groupname.wa, where groupname is the file containing the presentation of
the group. For the input format for files, the best thing at first is to
look at some of the files in automata.d/testdata and copy them.
One change from earlier versions is that, if you wish to use the convention
that inverses of generators are derived by case change (a = inverse of A, etc.)
then you must insert a line
inverses {case_change}
after the list of generators. Otherwise, the inverse of a will be called
a^-1  by default.

testisom takes as input two finitely presented groups and attempts to
decide whether they are isomorphic or not. It alternately attempts to
construct an explicit isomorphism, and (if this fails) to prove nonisomorphism
by finding distinct finite quotients of the two groups.

There are test packages for these two programs called testautomata and
testtestisom. These should be run from the directories automata.d/testdata
and isom.d/testdata respectively. Most of the runs in these packages are
quite quick, but a few are longer, so the test packages should preferably
be run overnight.

Please report any bugs, difficulties or suggestions to Derek Holt.
(dfh@maths.warwick.ac.uk). The programs were written by David Epstein,
Derek Holt and Sarah Rees.
