How to split a number in MATLAB?

Which are some of the programs written in Matlab involving  large number of matrix operations, I am basically trying to use an external library like BLAS or MTL4 and replace the existing matrix computation with method calls to these HPC libraries and compare the performance?

• Any pointers where I can find large matlab programs used in scientific applications would be appreciated.

• Answer:

  I'm guessing you're looking for things that are freely available. A couple of things come to mind. There's the N-way Toolbox (http://www.mathworks.co.uk/matlabcentral/fileexchange/1088-the-n-way-toolbox) that's available on the MATLAB Central File Exchange. This is a suite of tools for carrying out many statistical routines that are extremely heavily matrix-intensive. There's a lot in there that requires not only matrices but tensors, which are stored as multidimensional arrays - MATLAB is typically much less efficient on these than on 2D arrays, so you may be able to perform some clever tricks to optimise it. The other would be some of the files associated with Cleve Moler's textbook Numerical Computing with MATLAB (http://www.mathworks.co.uk/moler/ncmfilelist.html). You can download both the book and the files from that list. Cleve (who in case you don't know is Founder of MathWorks and a numerical analysis prof) obviously writes fairly tight code numerically, so if you can optimise that you'll be doing well.