ProjectSICStus Prolog - Leading Prolog Technology

SICStus Prolog - Leading Prolog Technology

SICStus Prolog is a state-of-the-art, ISO standard compliant, Prolog development system.

SICStus is built around a high performance Prolog engine that can use the full virtual memory space for 32 and 64 bit architectures alike. SICStus is efficient and robust for large amounts of data and large applications.


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SICStus Prolog Keeps the World Flying

SICStus Prolog is a workhorse in the transport and logistics industries, running systems that handle a third of all airline tickets, and helping railways to operate their trains better.

Transport and logistics is one of the big applications for SICStus Prolog. In other languages, you express what should be done. By contrast, a Prolog program defines a set of facts and rules, and lets the Prolog engine compute the correct answer. In the case of airline ticketing, there are rules for which airlines offer good prices to passengers from other airlines, how much time is needed for a connecting flight depending on the airport, terminal, time of day, etc. In effect, the Prolog system is used as a an engine to process rules, and the programming of the system is greatly simplified.

“Most people probably have used SICStus Prolog without knowing it,” says Mats Carlsson, its lead developer. “One of our customers runs a flight booking system on SICStus which handles nearly a third of all airline tickets in the world.”

SICStus also has an award-winning extension for constraint programming, which is used to compute a set a possible solutions to a given problem. This is often used as one of the steps in an optimization process. This has been used by Tacton Systems, itself a spin-off from SICS, to build sales configuration systems for complex products such as industrial electrical engines and forklifts. Another application for the combined use of Prolog and constraint programming is SICS’ own work in the railway sector, where it has been used to reduce the need for locomotives and to optimize track utilization.

Another application for SICStus Prolog is natural language processing. NASA used SICStus Prolog for a voice-controlled system onboard the International Space Station, ISS.

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