Re: libSVM support in Octave

[Bill Denney]

Schloegl Alois wrote:
> Trying the run the function like this,
>
>   model=svmtrain([1:100]'>50,randn(100,6),'-s 0 -c 1.000000 -t 0 -d 1');
>
> results in this error message:
>
> error: feval: the symbol `transpose' is not valid as a function
> Error: can't convert libsvm model to matrix structure: cannot  
> transpose SV matrix
>
> This message is caused probably due to this sequence
>   in svmtrain.c (line 263-265)
>          // transpose instance matrix
>                  if (mexCallMATLAB(1, plhs, 1, prhs, "transpose")) {
>                          mexPrintf("Error: cannot transpose training  
> instance matrix\n");
>
>
> Before I dig into the code the find a workaround, I'd like your answer  
> to the following questions.
>
> - Is it correct that the functon mexCallMATLAB is not supported in the  
> Octave-MEX interface?
> - if the answer is yes, are there any plans to implement it or is  
> there an alternative function ?
>   
Other people can probably answer this more definitively, but my reading 
of this is that it's trying to execute a function called transpose which 
doesn't exist.  Does it still fail if you put a file called transpose.m 
in the path that just does this:

function x = transpose(x)
 x = x';
endfunction

If that works, then we probably need to add a function like that into 
the octave distribution for compatibility.

Bill