A number of geographical analysis such as for transportation planning (demand forecasting), spatial interaction, accessability studies also known as gravity models depend on first computing distances between a set of locations. OD is the first step for such analysis. A number of analytical tools such as the Traveling Salesman Problem, Vehicle Routing Problem, Location-Allocation also start with first computing the OD and then look for a solution.OD can be computed and exported for use in third party Linear Programming packages for solving any type of optimizing problem. One such demonstration is the Allocation Tool that you can access here:http://resources.arcgis.com/gallery/file/Geoprocessing-Model-and-Script-Tool-Gallery/details?entryID...Jay Sandhu
