1.  NAME

  prefabs1 - Plot absolute velocities from reference layer

  2.  SYNOPSIS

  prefabs1(file, psf, year, cruise, note )

  3.  DESCRIPTION

  This function reads the output generated by refabs, and generates
  plots of the absolute reference layer velocities. It also calculates
  the time span and gap ratio parameters which are used in smoothr.

  4.  PARAMETERS

     file
        Name of input file (output of refabs).

     psf
        Name of output postscript file.

     year
        Year base used for decimal days in input file.

     cruise
        Name of cruise.

     note
        Additionnal note to print on plot.

  5.  GLOBAL VARIABLES

  The following variables must be defined before calling this function:

     min_speed
        Minimum allowed speed,in m/s. This should be the same value that
        will be used later in smoothr.

     max_speed
        Maximum allowed speed,in m/s. This should be the same value that
        will be used later in smoothr.

     ens_time
        The ensemble time length,in minutes.

  6.  SEE ALSO

  prefabs(1m) prefabs1(3m) prefabs2(3m) preflyr(1m) preflyr1(3m)
  preflyr2(3m) psmooth1(3m) psmooth2(3m) psmoothr(1m)

  7.  AUTHORS

  Pierre Jaccard, Geophysical Institute, University of Bergen, 1999