For formatting tutorial, read this: http://www.mathworks.com/matlabcentral/answers/13205-tutorial-how-to-format-your-question-with-markup Basically paste, highlight, then click {}Code.
To draw a line on your image:
hold on;
[rows, columns, numberOfColorChannels] = size(yourImage);
midColumn = columns/2;
line([midColumn, midColumn], [1, rows], 'Color', [.8, .7, 0.1]);
You can change the color and location if you want.
