> gtptest  gtptest evfile=my_pulsar_events_phase_v3r1.fits \
            outfile=gtptest-example-1.fits numphase=10 numharm=10 maxharm=10

    This command produces an output message that describes the types
    and the parameters of the periodicity tests that are performed,
    and explains the test results.  A plot will also be produced,
    which shows a folded-light curve used in the chi-squared test.