Looking for Matricies with their R-Echelon Forms

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Hi all,

I'm testing out a matrix solving program and while it checks out for 2x2/3x3/4x4 I would like to try it out on some larger matrices, but I don't really want to go through the hassle of row reducing a couple of 10x10 matrices to double check my program.

Does anyone happen to know of a website with matrices and their reduced echelon forms? Hopefully some with sizes > 5x5 (the maximum size is only restricted by memory, but past 25x25 I get visual errors).

Thanks!
 
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Octave (http://octave.sourceforge.net/) will do this for you.

Example:
Code:
12 > A = randn(5,7)
A =

  -1.168059   1.379002   1.050133   1.174869   0.241811  -1.207374  -0.879474
  -1.069804  -0.276065  -0.122203   0.106788  -0.868123  -0.376758   0.843255
  -0.254340   1.737628   0.500414  -0.232824  -0.963609  -1.475793   0.405880
  -1.008958  -0.018789   0.523780   0.369066  -0.010553  -1.382835   0.084481
   0.858681  -2.586128   0.415349   0.538282   0.834653  -0.063377  -0.128834

13 > rref(A)
ans =

   1.00000   0.00000   0.00000   0.00000   0.00000   0.66988  -0.17216
   0.00000   1.00000   0.00000   0.00000   0.00000   0.20572  -0.33145
   0.00000   0.00000   1.00000   0.00000   0.00000  -2.44269   0.18477
   0.00000   0.00000   0.00000   1.00000   0.00000   1.56390  -0.54221
   0.00000   0.00000   0.00000   0.00000   1.00000   0.07930  -0.74650
 
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