    MC-REWEIGHT:  Copy part of a log file while changing iteration weights.

    MC-reweight operates much like log-copy except that it also changes
    the weights for iterations by altering the records of type 'i'.  This
    allows the iterations to be changed so as to produce an importance
    sampling estimate for some distribution other than the one originally
    sampled, provided a program for computing the appropriate weights has
    been written.

    Usage:

       mc-reweight logfile-in range logfile-out < file-of-log-weights

    Records with negative indexes or with indexes in the indicated range
    are copied from logfile-in to a newly-created logfile-out, except that
    records of type 'i', which record information on Monte Carlo
    iterations, are altered by adding values read from standard input to
    the log weights recorded in these records.  The range has the usual
    [low][:[high]][%modulus] form, as described in parse_range in misc.c.
    If high and the colon are omitted, high defaults to low.  If high is
    omitted but the colon is present, the range extends to the end of the
    file.

                Copyright (c) 1995-2004 by Radford M. Neal