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Re: MATLAB file format support

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  • Subject: Re: MATLAB file format support
  • Date: Wed, 11 Jan 1995 05:55:11 -0700
> Organization: Biophysics Lab., University of Nijmegen, The Netherlands

Hi,

> Is there any conversion software available to convert any of the
> formats mentioned in this group to the MATLAB format and vice versa?

Yes, there is software for importing netCDF data into MATLAB.  Here's the
excerpt from http://www.unidata.ucar.edu/packages/netcdf/utilities.html

MATLAB Interface

   An interface between Matlab and NetCDF called MEXCDF has been
   developed by Chuck Denham at the US Geological Survey in Woods Hole.
   
   MATLAB is a software package that integrates numerical analysis,
   matrix computation, signal processing and graphical display.
   
   MEXCDF is a complete interface between netCDF and MATLAB that uses the
   MATLAB mexfile utility to allow MATLAB users to read, write, and
   manipulate netCDF data files in an efficient manner, following the C
   language interface syntax found in the netCDF 2.3 users manual. In
   addition, the interface has been enhanced in several ways:
   
     * Dimensions and variables accessible by number or name.
     * Attributes accessible by number or name.
     * Parameters accessible by number or name.
     * Prepended "nc" not necessary for operation names.
     * Prepended "NC_" not necessary for specifying parameters.
     * Parameter names not case-sensitive.
     * Required lengths default to actual lengths via -1.
     * AutoScaling via "scale_factor" and "add_offset" attributes.
       
   As an example, to read the following 2D array 'elev' in file
   'foo.cdf',
   
              short elev(lat, lon)
                 elev:scale_factor=100.
                 elev:add_offset=0.,

   the required MATLAB commands using mexcdf are simply:
   
    mexcdf('open','foo.cdf','nowrite');
    elev=mexcdf('varget',cdfid,'elev',[0 0],[-1 -1]);
    mexcdf('close');

   The edges values "-1" means get all the values in this dimension, and
   scale_factor and add_offset are handled automagically by varget.
   
   For more information regarding this software, get the file
   /pub/mexcdf/README via anonymous ftp from crusty.er.usgs.gov
   (128.128.19.19) or contact Rich Signell at
   address@hidden.

______________________________________________________________________________

Russ Rew                                                UCAR Unidata Program
address@hidden                                          P.O. Box 3000
http://www.unidata.ucar.edu/                          Boulder, CO 80307-3000
______________________________________________________________________________