In previous work (Nicodème et *al.* 1999), we considered algorithms related
to the statistics of
word occurrences and regular expression occurrences in texts
generated by Bernoulli or Markov sources.
In this work these algorithms are extended for two purposes:
to determine the statistics of simultaneous counting of different
motifs, and to compute the waiting time for the first match with a motif
in a model which may be constrained.
This extension also handles
matches with errors. The package is fully implemented and gives access
to high and low level commands.
We also consider an example corresponding to a practical biological
problem: getting the statistics for the number of matches of words of size
8 in a genome (a Markovian sequence), knowing that an (overrepresented
DNA protecting) Chi
pattern occurs a given number of times.