3.5.2 Looking at the output

The ``traditional'' or mdsio model data are written according to a ``meta/data'' file format. Each variable is associated with two files with suffix names .data and .meta. The .data file contains the data written in binary form (big_endian by default). The .meta file is a ``header'' file that contains information about the size and the structure of the .data file. This way of organizing the output is particularly useful when running multi-processors calculations. The base version of the model includes a few matlab utilities to read output files written in this format. The matlab scripts are located in the directory utils/matlab under the root tree. The script rdmds.m reads the data. Look at the comments inside the script to see how to use it.

Some examples of reading and visualizing some output in Matlab:

% matlab
>> H=rdmds('Depth');
>> contourf(H');colorbar;
>> title('Depth of fluid as used by model');

>> eta=rdmds('Eta',10);
>> imagesc(eta');axis ij;colorbar;
>> title('Surface height at iter=10');

>> eta=rdmds('Eta',[0:10:100]);
>> for n=1:11; imagesc(eta(:,:,n)');axis ij;colorbar;pause(.5);end

Similar scripts for netCDF output (rdmnc.m) are available and they are described in Section 7.2.

The MNC output files are all in the ``self-describing'' netCDF format and can thus be browsed and/or plotted using tools such as:

• ncdump is a utility which is typically included with every netCDF install:

  http://www.unidata.ucar.edu/packages/netcdf/
  

  and it converts the netCDF binaries into formatted ASCII text files.

• ncview utility is a very convenient and quick way to plot netCDF data and it runs on most OSes:

  http://meteora.ucsd.edu/~pierce/ncview_home_page.html
  

• MatLAB(c) and other common post-processing environments provide various netCDF interfaces including:

  http://mexcdf.sourceforge.net/
  

  http://woodshole.er.usgs.gov/staffpages/cdenham/public_html/MexCDF/nc4ml5.html
  

Copyright © 2006 Massachusetts Institute of Technology

Last update 2011-01-09