fast string searches

[rutiger bishop]

Does anybody know of any tricks or optimized functions
for pattern matching in strings? An example of what I
am talking about is the following:

debug> tic; indx = strmatch('sensor x velocity at
aperture center (DUNITS, PCS)', value_name ); toc
Elapsed time is 0.115318 seconds.

In MATLAB, however:

K>> tic; indx = strmatch('sensor x velocity at
aperture center (DUNITS,PCS)', value_name ); toc
Elapsed time is 0.001158 seconds.

So Octave is 100 times slower than MATLAB in this
case. I can speed it up by using this instead:

debug> tic; indx = find( strcmpi('sensor x velocity at
aperture center (DUNITS, PCS)', value_name ) ); toc
Elapsed time is 0.049141 seconds.

K>> tic; indx = find( strcmpi('sensor x velocity at
aperture center (DUNITS, PCS)', value_name ) ); toc
Elapsed time is 0.000227 seconds.

MATLAB is still amazingly faster. I haven't found
anything on the Octave mailing lists yet, so I am at a
loss. This problem is causing a function that executes
in 20(sec) in MATLAB to execute in what seems like
5(min) in Octave.



 
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