Differences between PRR and CAROUTE

The primary difference between the two systems is how they route cars. Planned Railroad Routing (PRR) is my original system and it is based on the industries requesting empties and shipping loads. Each industry has a list of 10 car types that it uses and 10 destinations that it ships to. The cars can all be the same, all different or any combination. An "industry" can be one spot or track in a bigger industrial complex, if desired. When an industry has a car loaded and ready to ship, PRR randomly selects from the list destinations for that industry. PRR checks to see if the destination accepts that car type and if it has space among other factors. Then PRR assigns the car to be moved from its current location to that destination. When an industry has an empty spot, based on % requests, PRR randomly selects from the car type list and then searches for the first empty car in the system that is not assigned. That car is then assigned to move to the industry. When all industries have been checked, the program goes through the car list and assigns each car to an appropriate train that will move it from its location to the assigned destination. If no train can be found, the car is forwarded to the first yard in the industry list. "Yards" are special industries that get empties and transfers. After all the cars are moved, the status (load/empty) of any car not in a yard is changed from load to empty or vice-versa.

CAROUTE is very much like the waybills in pockets in cards systems that are so common. In CAROUTE, each car has a list of up to 20 possible destinations. When a session is run, the program assigns the car to move from its current location to the next destination on its list. The "waybill" has load/empty status on it for each destination, so a car can go as a load from A to B to C if you want. It does similar checks for trains like PRR. In PRR, industries are located in "towns" and trains serve towns. In CAROUTE, trains are assigned specific industries to serve.

Both programs allow layovers causing a car to stay in the industry until the number of layover sessions have been run. Both systems maintain all data once it is entered. You never have to re-enter data for each session. You only have to enter data when you want to modify your systems. In both programs, "industries" and "towns" specified in the data are logical entities you set up to define how your trains service them. Real physical towns and industries may be broken down and entered separately to create the operating assignments you want to describe.

Both programs print out switchlists for each train and optionally switchlists for each town. The town switchlists display information only for the trains you specify for the town. The data entry concepts and planning for PRR are much more indirect. You have to think in terms of what industries request/ship what cars to cause car movement. You think in terms of which towns' trains serve to provide industry service.

The data entry concepts for CAROUTE are more direct. For CAROUTE, you specify for each car which industries it goes to. Moreover, in CAROUTE you assign trains to service individual industries rather than towns.

Whichever product you choose, I am sure it will reduce the amount of time you spend preparing for your operating sessions and make them more interesting as well.