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Blog tag constraint

Constraint Streams - Modern Java constraints without the Drools Rule Language

Tue 7 April 2020

 Geoffrey De Smet

Traditionally, to scale out with OptaPlanner, you had to learn DRL. No more. With the new Constraints Streams API, inspired by Java 8 Streams and SQL, you can now write your constraints in Java (or Kotlin or Scala) and still benefit from incremental calculation. Underneath, Constraints Streams (CS) still use the powerful Drools engine. We also...

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Formula for measuring unfairness

Fri 3 February 2017

 Geoffrey De Smet

Load balancing is a common constraint for many OptaPlanner use cases. Especially when scheduling employees, the workload needs to be spread out fairly. Easier said than done. Let’s take a look at this challenging problem. For example, let’s assign 15 undesirable tasks to 5 employees. Each task takes a day, but they have different...

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  • 8.1.0.Final released
    Fri 15 January 2021
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    Worldwide - Tue 19 January 2021
    • OptaPlanner Shadow Variables for the Vehicle Routing Problem and Task Assignment by Geoffrey De Smet, Karina Varela, Alex Porcelli
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    Worldwide - Tue 16 March 2021
    • AI on Quarkus: I love it when an OptaPlan comes together by Geoffrey De Smet
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  • Solve the facility location problem
    Fri 9 October 2020
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    Mon 7 September 2020
     Geoffrey De Smet
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    Fri 3 July 2020
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  • AI versus Covid-19: How Java helps nurses and doctors in this fight
    Fri 8 May 2020
     Christopher Chianelli
  • Workflow processes with AI scheduling
    Tue 5 May 2020
     Christopher Chianelli
  • Constraint Streams - Modern Java constraints without the Drools Rule Language
    Tue 7 April 2020
     Geoffrey De Smet
  • How to plan (and optimize) a Secret Santa
    Wed 18 December 2019
     Christopher Chianelli
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Latest videos
  • YT Shadow variables
    Tue 19 January 2021
     Geoffrey De Smet
  • YT Domain modeling and design patterns
    Tue 17 November 2020
     Geoffrey De Smet
  • YT Quarkus insights: AI constraint solving
    Tue 20 October 2020
     Geoffrey De Smet
  • YT AI in kotlin
    Wed 23 September 2020
     Geoffrey De Smet
  • YT Planning agility: continuous planning, real-time planning and more
    Thu 3 September 2020
     Geoffrey De Smet
  • YT Quarkus and OptaPlanner: create a school timetable application
    Thu 3 September 2020
     Radovan Synek
  • YT Business use cases and the impact of OptaPlanner
    Thu 3 September 2020
     Satish Kale
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