Matlab script for digitizing a published graph

User needs to load the image into matlab workspace before running this program.
User needs to provide the name of the image, and the number of data points to be digitized. The user will be asked to indicate on the image the pixel position corresponds to the origin, a value on x axis and a value on y axis. These are used to scale the user selected data points.

usage exampe:digitizeGraph(testGraph,3);