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====Matlab====

===Tutorials===

  *[[http://www.mathworks.com/academia/student_center/tutorials/launchpad.html|Matlab Tutorial Center]]: videos and interactive tutorials from Mathworks

   *[[http://people.aero.und.edu/~gretchen/matlab/|Introduction to Matlab]] by Gretchen.  Note that netCDF toolbox referenced in Introduction is outdated as of Matlab R2008b.  netCDF toolbox now embedded and follows C Library toolbox.

   *[[http://people.aero.und.edu/~gretchen/mat_tut/|scripts]] discussed at Advanced Matlab Workshop (Aug. 18, 2011)

   *[[http://www.mathworks.com/moler/exm/chapters.html|Experiments with Matlab]]: some awesome experiments to conduct using Matlab (including shallow water equations)!

===== PHIPS Image Classifier using MATLAB ======
   * [[atmos:software:matlab:PHIPS_Classifier|PHIPS Image Classifier]]



===Notes on new netCDF toolbox===

  * If //ncdump// gives dimensions of //(time,yc,xc)//, //netcdf.getVar// wants the variables accessed in flipped order.  For example: 
''netcdf.getVar(file_id,var_id,[xc_start yc_start time_start],[xc_count yc_count time_count]);''
  * The toolbox uses indices that start count at **zero**!  So, if using //start// array for //netcdf.getVar// call, be cautious.  Once matrix loaded, go back to normal Matlab indexing, which starts at one.

===Notes on Plotting Dimensions===

For two-dimensional plots (e.g. contour), Matlab wants the "size" of the matrix to be NxM, not MxN.  For example, say I have a matrix "test".

''size(test)''

''ans = 97 80''

If I execute the plot command,

''contour(x(1:97),y(1:80),test);''

  Matlab will give me an error about the size of my dimensions being mismatched.

Instead, you have to transpose the matrix for the plot to look as expected.  Notice the single quote after the matrix name below.

''contour(x(1:97),y(1:80),test');''

**Be careful of all two-dimensional functions in Matlab, as I often find that NxM is expected!**  If in doubt, make your dimensions different sizes for tests, then you won't mistakenly be accessing the x-dimension when you mean the y-dimension (or vice-versa).
=== Matlab comment wrapping ===
Ever write comments so long that they wrap around to another line, but you have plenty of screen left and want to keep them all on the same line? Here is how to turn comment wrapping off:
  - File -> Preferences -> Editor/Debugger -> Language
  - Uncheck the 'Autowrap comments' box
(Dan Ariaansen via http://www.mathworks.com/matlabcentral/newsreader/view_thread/236138, 06-09-09) 

===Matlab Research Licenses===

The UND Atmospheric Sciences Department has floating research licenses that allow installation of Matlab on your research computer.  Contact Gretchen for more information.

The UND CRC also has some licenses: these licenses include more toolboxes, including the Parallel Computing Toolbox. 
\\ [[.crc|CRC License Information]]

===Google Earth Toolbox===

[[http://www.mathworks.com/matlabcentral/fileexchange/12954|Google Earth Toolbox]]
(I haven't tried this yet, but looks promising- Gretchen)

I have used this toolbox a lot.  Works great!  Come by my office and I can show you some results. - Chris Theisen