  1.  NAME

  info_nav - Get navigation information from ADCP files

  2.  USAGE

  info_nav [options] format

  3.  DESCRIPTION

  This Perl utility reads ADCP data files and prints information about
  navigation. It is especially useful for grouping the adequate ADCP
  profiles with their corresponding CTD sections.

  Name of navigation files are expected to be listed on the standard
  input. Hence, a pipe or input redirection is required. Output is
  written to standard output. The specified output format determines
  what information to read and how to print it. Possible keywords are:

     file_time_range
        Print the time range spanned by each input file.

     transect_time_range
        Print the time range spanned by each transect. This format
        expects the file name convention of TRANSECT.

  4.  OPTIONS

  The following options are implemented:

     -t type
        Specify the input files type and how to get the navigation data.
        Possible values are:

        gga
           Input file is an NMEA file, and the navigation information
           should be taken from the GGA string.

  5.  AUTHOR

  Pierre Jaccard, Geophysical Institute, University of Bergen, 1999.

