I have to visualize the path of the longest common substring in a matrix.
But I don't get it to draw, plot or whatever the matrix containing values.
And the path is also a big problem.
It should look like this picture:
http://www.nabble.com/file/p13710192/alignment5.gif
Your requirement is for a pretty specific graphics-related job---
Octave is a computational environment, not a graphical environment. I
haven't seen an Octave graphing package that does what you asked
for. If I had to do it, I'd write Octave code to emit instructions for
a separate graphing program such as xfig:
http://www.cs.virginia.edu/helpnet/Authoring_Tools/xfig/FORMAT2.1.html
and then ran that program to render the graph.
However, that only makes sense if you need Octave to calculate the
numbers, and the output part is incidental. Otherwise, you'd cut out
the middleman and print xfig commands directly from whereever you
are getting your numbers from.