1.  NAME

  sgeo - Calculate geostrophic slope

  2.  USAGE

  sgeo

  3.  DESCRIPTION

  Read geostrophic current data from a grid ascii file, as output by C
  utility vgeo(1) and compute the corresponding slope heights. Generate
  a plot for each of the specified depths and save data into an ascii
  file.

  The input file must contain the following columns:

  1. Time in decimal days

  2. Longitude in degrees

  3. Latitide in degrees

  4. Depth in meters

  5. Geostrophic current

  This Matlab script is an interface to function sgeo_grd(3m).

  4.  PARAMETERS

  The following parameters must be edited:

     vgeo_file
        Name if input file with geostrophic current data.

     out_file
        Root name of output file. Suffixes are automatically added.

     year_base
        Base year used to determine the decimal days in the input file.

     x_axis
        Column number to x-axis for plotting. It must be one of 1,2 or
        3. If negative,the axis direction will be reversed.

     slope_0
        Initial slope value in meters.

     vgeo_scale
        Factor to get geostrophic currents from input file in m/s.

     sgeo_scale
        Scaling factor for plotting slope height points.

     vgeo_dir
        The direction that was used to compute the geostrophic current.
        This is necessary in order to get the correct slope variations.
        This is one of northward,southward,westward of eastward.

     depths
        Array with depths values at which plotting of slope heights is
        desired.  The values must be present in the input file (i.e. no
        interpolation is carried out here). If empty,all available
        depths in the input file will be plotted.

     title
        Title of plot.

     info
        Additionnal information string.

     institute
        Institute stamp.

  5.  OUTPUT

  The following files are generated:

     out_file.ps
        Postcript output of plot.

     out_file.asc
        Ascii data of slope height values.

  6.  AUTHORS

  Pierre Jaccard, Geophysical Institute, University of Bergen, 1999