MATLAB: What is repmat() doing in the following code

matlab function

function handles = Open_Image(hObject, eventdata, handles, type, axesIm)
    % if the file-name and path-name are not epty. 
    if not(isequal(handles.file, 0)) && not(isequal(handles.path,0))
        % the current axes should be set to handles.axes
        axes(handles.axes);
          % Extract image and colormap from file path
          [handles.img, handles.map] = imread([handles.path handles.file]);
          % Viewing the image
          [n,m,l] = size(handles.img);
          % with bidimensional images, image does not work properly
          if (l == 1) 
              image (repmat(uint8(handles.img),[1 1 3]));
          else
              image(handles.img);
          end
          axis equal; % sets the aspect ratio. (Show the image in its right ratio)
          axis tight; % Sets the axis limits to the arrange of the data.
          axis off; % Turn off all axis labeling          
          guidata(hObject, handles);
      end

Best Answer

repmat does exactly, what is explained in the documentation. See doc repmat:
The contents of the array handles.img is repeated 3 times along the 3rd dimension. This will create an RGB image in grey color from the matrix in handles.img.
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