how to use cvCreateTestSet

asked 2013-03-02 09:59:12 -0500

Fabien R gravatar image

updated 2013-03-03 05:36:42 -0500

I'm trying to generate test samples for MLP (OpenCV 2.3).

I found the function cvCreateTestSet in ml.hpp but I did not see explanations about how to use it.

Any hints ?

Edit: I would like to adapt this excellent wiki by replacing kMeans by MLP(back_prop). I was wondering if cvCreateTestSet could be used somewhere in the process.

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Comments

it might help, if you could be more specific, about how you want to use that mlp.

what does your input look like ?

are you trying to do some classification ? are there 2 'classes' or more ?

for training, the mlp wants 2 things:

* a set of input 'examples', either as a Mat with 1 row per sample, 
  or as a vector of 1 row samples,
  ( the size of the colums being the number of your input nodes ) 
* and a vector of (float) labels, same size as num samplerows.
  ( there's a  label for every output node, and each input sample belongs to exactly one label )

there's a lot of ways to get that data, be a bit more specific, so ppl here can help you better ;)

berak gravatar imageberak ( 2013-03-02 15:24:13 -0500 )edit

Sorry for the short post. I edited the question.

Fabien R gravatar imageFabien R ( 2013-03-03 05:37:35 -0500 )edit
1

oh, that's a nice wiki link.

looking at the code ( ml/src/testset.cpp, 59 ) it seems, i's constructing a very special set of randomized inputdata for the case of CV_TS_CONCENTRIC_SPHERES (what's that ? no idea.)

so, it CONSTRUCTS random features.

not what you wanted, i guess

please, have a look here, too. rosetta-stone like approach at comparative implementations of ml techniques (including mlp):

http://www.bytefish.de/wiki/machine_learning_opencv

berak gravatar imageberak ( 2013-03-03 05:49:01 -0500 )edit

Thanks berak. For the moment, I think I will stick to what everyone does, i.e., removing a part of the training sample set to feed the testing process.

Fabien R gravatar imageFabien R ( 2013-03-09 10:13:51 -0500 )edit