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train and test data using KNN classifier

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HI I want to know how to train and test data using KNN classifier we cross validate data by 10 fold cross validation. there are different commands like KNNclassify or KNNclassification.Fit. Don't know how to accomplish task Plz help me Thanks
  1 Comment
Kathryn Hollowood
Kathryn Hollowood on 12 Mar 2019
That he just shared also includes information about predicting the classification using knn. So you use the fitcknn to create the model (Mdl). So it would be like:
class = predict(Mdl, TestCase).
This should hopefully give you what you are looking for.

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Accepted Answer

Shashank Prasanna
Shashank Prasanna on 18 Jul 2013
Have you tried out the examples in the documentation?
I don't think we can help you any better than the examples in the doc. If you have specific questions then we can address that.
  1 Comment
sehrish
sehrish on 19 Jul 2013
Yes Shashank I have tried it but I could not understand where are its training and testing results? here is the code
% Classify the fisheriris data with a K-Nearest Neighbor classifier
load fisheriris
c = knnclassify(meas,meas,species,4,'euclidean','Consensus');
cp = classperf(species,c)
get(cp)
% 10-fold cross-validation on the fisheriris data using linear
% discriminant analysis and the third column as only feature for
% classification
load fisheriris
indices = crossvalind('Kfold',species,10);
cp = classperf(species); % initializes the CP object
for i = 1:10 test = (indices == i); train = ~test;
class = classify(meas(test,3),meas(train,3),species(train));
% updates the CP object with the current classification results
classperf(cp,class,test)
end
cp.CorrectRate % queries for the correct classification rate

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More Answers (1)

snehal jaipurkar
snehal jaipurkar on 26 Jan 2018
Sir please reply soon.... can we use eucledian distance and hamming distance both in knn classifier at the same time??? I am working on a project where I have to classify gabor features using hamming distance and geometrical features using eucledian distance..... Is it possible sir?????

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