SVM Classifications on set of images of digits in Matlab

Question

I have to use SVM classifier on digits dataset. The dataset consists of images of digits 28x28 and a toal of 2000 images. I tried to use svmtrain but the matlab gave an error that svmtrain has been removed. so now i am using fitcsvm.

My code is as below:

labelData = zeros(2000,1);

for i=1:1000
labelData(i,1)=1;
end

for j=1001:2000
labelData(j,1)=1;
end

SVMStruct =fitcsvm(trainingData,labelData) 
%where training data is the set of images of digits.

I need to know how i can predict the outputs of test data using svm? Further is my code correct?

max max · Accepted Answer · 2019-12-14T13:24:42

The function that you are looking for is predict. It takes the SVM-object as input followed by a data-matrix and returns the predicted labels. Make sure that you do not train your model on all data but on a reasonable subset (usually 70%). You can use the cross-validation preparation:

% create cross-validation object
cvp = cvpartition(Lbl,'HoldOut',0.3);
% extract logical vectors for training and testing data
lgTrn = cvp.training;
lgTst = cvp.test;

% train SVM
mdl = fitcsvm(Dat(lgTrn,:),Lbl(lgTrn));

% test / predict SVM
Lbl_prd = predict(mdl,Dat(lgTst,:));

Note that your labeling produces a single vector of ones.

The reason why The Mathworks changed svmtrain to fitcsvm is conciseness. It is now clear whether it is "classification" (fitcsvm) or "regression" (fitrsvm).

SVM Classifications on set of images of digits in Matlab

1 Answers