Routing Preferences, or parameters, help DirectRoute determine the ‘how’ to route, or routing environment, which may include various constraints (work rules, travel restrictions, delivery windows, available equipment, etc.) that must be followed.


Routing Preferences are used to supply the software with necessary information about your routing environment and the type of results expected in the routing solution. These settings help DirectRoute identify specific data fields, volume types, and delivery windows used in the Truck File and Stop File, and direct specific actions, behaviors, or special considerations that the software should perform or consider when building routes.


Tip: Upon initial installation of the DirectRoute software program, the assigned Appian Implementation and Training Consultant will help identify and update all settings that best fit your specific routing environment.


The Routing Preference and Options Table identifies and explains each setting and available options more completely. To access and update Routing Preferences in DirectRoute, select File > Preferences from the main menu. 


While all the preference settings are important to each routing solution, some settings are more critical and dependent on your routing environment, and some settings may not be used at all. Preference settings are divided into multiple sections, as briefly identified below.

  • Configuration: Settings specific to the Truck and Stop Files.
  • Defaults: Default options are applied during the extract process.
  • DRTrack: For DRTrack users; identify URL paths and IDs for uploading routes.
  • ETS Provider: For users of TMW ETS or TMW Innovative services.
  • Extract: Extract settings for use with an Order Management/Host system.
  • File Names/Paths: Identifies location paths of key files used in the routing process.
  • Geocode Options: Select Secondary Geocode processes and options (ex. Google). 
  • Import: Settings used to import XML Files from integrated TMW Systems software.
  • Mode Selection: Options used in conjunction with Transportation Modeler software.
  • Other: Identify mileage system and custom Geocode Files or special Map Files to use.
  • PC*MILERRouting and vehicle options for use WITH a PC*MILER license.
  • PC*MILER Direct: Routing and vehicle options for use WITHOUT a PC*MILER license. 
  • PostProcessAccelerates after-routing processes when Upload Files is used.
  • PreprocessAccelerates the routing process with selected automatic actions.
  • Routing: Options used in the automatic load building and optimization processes.
  • Tanker: Load building options for compartments, used with the Tanker Algorithm.
  • Trimble Maps: Route and Distance File options for use with PC*MILER Web Services.
  • Update Stop File: Select Stop Fields to update automatically during the Upload process.
  • Upload: Upload settings for export to an Order Management/Host system.


Lambda and Lambda Values

Lambda is a variable factor that controls how much weight to give a potential stop based on how far it is away from a depot (cone expansion vs. distance from the depot) during the loading phase of the algorithm. The routing algorithm uses lambda when it is deciding on which stop to load on a route next.


Lambda Values are typically between 0.5 and 2.0, depending on the density of the stops in your delivery area (a high density of stops usually calls for a lower Lambda value). 

  • The default setting for Lambda is 2, which provides the best results over a large range of problem types.
  • Setting Lambda Value to less than 2 will cause DirectRoute to build tighter routes (less expanded cone) but might result in an overall increase in miles. 
  • For high stop count routes (very dense), you might consider lowering the Lambda Value, but it would be best to run a few scenarios with various Lambda Values (1 thru 1.5) to determine the right number.
Example: Assume that the depot is represented by the green diamond and the three red dots are stops to be routed. Each stop has a volume equal to one half of a vehicle’s capacity. Given this set of facts, it will require two vehicles to service the three stops. The algorithm will typically load the farthest stop from the depot first, in this case that is Stop A. The next decision is to determine which of the remaining stops to load. This decision is based on a combination of how much mileage the prospective stop will add to a route and how far the stop is from the depot times the Lambda factor.


If Lambda were set to zero (thereby giving no weight to how far the stop is from the depot) the stop selected to be loaded next, would be Stop C, since it adds almost no additional mileage to a route already going to Stop A. This vehicle would now be full and require the second route to service Stop B. This solution would have higher miles than the solution that paired Stops A and B, and a second route containing Stop C.


The following (High Lambda, Low Lambda) depict two sets of routes running the same stops with low and high Lambda Values:

You can see that the routes ran with the higher Lambda attempt to pick up the stops farther away from the depot. Although the high Lambda routes may not look as good as the low Lambda routes they are actually 3% fewer miles because they are only running two trucks to the outer perimeter stops (the red and black routes) versus three routes in the low Lambda scenario. 


To edit Lambda settings, select from the DirectRoute menu: File > Preferences > Other. There are three values to set; experiment with the value of Lambda and decide which setting is best for your routing environment:

  • Lambda Setting: Specifies the initial value of Lambda, or the value of Lambda to use for running Iteration 1; the default value is 2 and ranges can vary from .1 up to 2.0.
  • Lambda Iterations; Number of times to calculate routes using increments.
  • LambdaIncrements–Value used to increase Lambda while calculating routes; allows several attempts at a routing solution that yields the lowest cost. 

Example: Suppose Lambda is set to 0.6 and Lambda Increments and Iterations were set to 0.2 and 4, respectively. DirectRoute will construct routes four times using Lambda Values of 0.6, 0.8, 1.0, and 1.2 and display the solution that yielded the lowest cost.

Tip: Once the best settings are discovered, the Iterations should be set back to 1. Keeping a higher iteration setting will cause the route to be re-run several times, even once the best Lambda Settings have been found.

Note: When using Redispatch, it is recommended that Lambda Iteration 1 be used.

Caution: When using Lambda with Iterations, and cancel is pressed, the user must cancel each of the iterations as they begin. When one is canceled, the next route begins to load.

Box Expand and Box Expand Values

Box Expand is a parameter that defines which routes are considered for between route optimization. During optimization, DirectRoute constructs the smallest box that will contain all the stops on a route. When DirectRoute considers making moves, the logic does not consider moving stops between routes, unless their boxes intersect. This includes routes that are in the same vicinity.


The Box Expand Value is represented in miles and determines how far to expand the box. Larger numbers increase the time it takes for the system to complete optimization; adjusting the parameter allows the system to consider more routes during optimization. 


The miles would be saved if Stop 4 (black route) was placed on the red route. By increasing the parameter to 25, the boxes now intersect, thus allowing more moves to be evaluated. The increased value of Box Expand will also increase the amount of time the system takes to complete the optimization process.


To edit Box Expand Values, select from the DirectRoute menu: File > Preferences > Other. Enter the number of miles to identify how far to expand the box.