How can I compare the SURF inliers?

I have to compare the inliers found through the SURF algorithm. For each inlier found in the frames of a video, if it is new I have to save the data and the frame where it was found otherwise I have to upgrade the data by adding the number of the frame where it was found again. My problem is when I do the for loop with if statement inside the loop: which parameters should I use to make sure that the program controls all inlier I found? This is my code:

   for f=lastFrame+1:10   % For each frame of the video (First I tried with the first 10 frames)

fGray= rgb2gray(read(videoObj,f));
fFlip=flipdim (fGray,1);

if f>1  % For each previous frame of the video (I have to compare each frame with his previous)

   f1Gray= rgb2gray(read(videoObj,(f-1)));
   f1Flip=flipdim (f1Gray,1);

refPoints = detectSURFFeatures(fFlip);
refPrePoints = detectSURFFeatures(f1Flip);

[refFeatures, refPoints] = extractFeatures(fFlip, refPoints);
[refPreFeatures, refPrePoints] = extractFeatures(f1Flip, refPrePoints);

      % matching
      featPairs = matchFeatures(refFeatures, refPreFeatures);

      matchedRefPrePoints = refPoints(featPairs(:, 1), :);
      matchedRefPoints = refPrePoints(featPairs(:, 2), :);

      %homography

      [tform, inlierRefPoints, inlierRefPrePoints] = ...
  estimateGeometricTransform(matchedRefPrePoints, matchedRefPoints, 'projective');

      disp(inlierRefPoints); % to view data

   % for each inlier found if it's new save it and reference frame, otherwise update frame data

   for i = 2:numel(inlierRefPoints)

       element = inlierRefPoints(i);
       elementPre = inlierRefPrePoints(i);

       mem =  ismember (element, elementPre);
     %  disp (element)
     %  disp (elementPre)

if mem==1 %  existing inlier

     disp(['Inlier ',num2str(element) ,'exists in frame ', num2str(f)]);

     else % new inlier
     disp(['Inlier ',num2str(element) ,' is NEW']);

     % Save data

end
end 

end
end