Determine class of image using neural network

I have written a code to detect face and give it to a trained network. Its work is to detect which face is it based on the training. I only get numbers between 49 and 50. I don't know what it means and how to use this number to get which image is it. During training the target set was numbers, different numbers for different images. I want the image number set during the training when testing my neural net. Here is my code to test my network :

function name = search( net, img )

    faceDetector = vision.CascadeObjectDetector();
    disp('Detecting face of input image.');
    bbox=step(faceDetector, img);
    max=1;
    for i=1:size(bbox,1);
        if(areaRect(bbox(max,:))<areaRect(bbox(i,:)))
            max=i;
        end
    end
    img=img(bbox(max,2):bbox(max,2)+bbox(max,4),bbox(max,1):bbox(max,1)+bbox(max,3));
    imshow(img);

    disp('scanning for result.');
    hs=im2vec(imresize(img,[27 18]));
    name=sim(net,hs)
end

function area = areaRect(rect) area=rect(3)*rect(4); end

Please help me with this.