6_tab:PerfectClub_satisfiability_exception_100 shows numbers
of exceptions for JANUS 64-bit, 
Simplex, Fourier-Motzkin and
Double Description method, and the number of tests in PerfectClub
sampled database. One notices that JANUS is more robust than
Simplex: 
to 
overflows. It has no timeout exception, while
Fourier-Motzkin raises 
timeout exceptions and Double
Description method raises overflows only and 
timeout
exceptions that may block our analysis. We notice that Fourier Motzkin
has no overflow exception.
With SPEC95, sampled database, we have another result: JANUS 64-bit
has more exceptions than Simplex (
to 
), and more than
Fourier Motzkin method ( to 
)
6_tab:SPEC95_satisfiability_exception_100. We also observe
that Fourier Motzkin method has 
timeout exceptions, and there are
many overflow exceptions with the Double Description method: 
.