SVM with different length features I need to train SVM with 2 different features..the problem is one feature is the HOG with length 144 and other an RGB value with length 3.. Can i combine these two features to train SVM  and test using the same? the code iam using is

X1=xlsread('train1.xlsx');
Y1=xlsread('CLASS1.xlsx'); 
svmStruct1=svmtrain(X1,Y1);
 classes=svmclassify(svmStruct1,test);


the test data contains both RGB and HOG values..
Yes, you can do it.  Concatenate the two feature vectors to get a single feature vector of length 147; the first 144 components are from the HOG, and the last 3 components are from the RGB.  Then apply the SVM on the feature vector of length 147.  SVM doesn't care where the individual numbers came from.

Code is off-topic on this site.