如何在Java中为PDDL用例建模

时间:2019-10-14 11:04:04

标签: java pddl

作为物流示例,我正在尝试将普通的PDDL案例建模为另一种编程语言(java)。我这样做是为了了解使用PDDL的优点或缺点。

这是PDDL的原始示例

https://github.com/pellierd/pddl4j/wiki/Logistics:-a-simple-running-example

我的结果是一个简单的顺序程序,如代码所示。我的目标是使计算自动化,以获得真正的组合计算,而不是顺序计算。

public class logistics {

private static boolean airplaneInUse = false;
private static boolean truckInUse = false;
private static String airport;
private static String place;
private static String city;
private static String pack1;
private static String pack2;

static int state = 0;



public static void main(String args[]) {


    if(state == 0) {

        start();
        System.out.println("The city in the initial state is " + city + "\n");
        System.out.println("The airport in the initial state is " + airport + "\n");


    }

     if(city == "London") {

        load_plane();
        System.out.println("pk1 and pk2 are on the plane" +"\n");
        pack1 = "On Board";
        pack2 = "On Board";

    }

    if(pack1 == "On Board" && pack2 == "On Board") {

        fly();

        System.out.println("The city after the flight is " + city + "\n");
        System.out.println("The airport after the flight is " + airport + "\n");

    }

     if (city == "Paris") {

        unload_plane();
        System.out.println("pk1 and pk2 are unloaded from the plane " + "\n");
        pack1 = "Unloaded";
        pack2 = "Unloaded";

    }

     if (pack1 == "Unloaded" && pack2 == "Unloaded") {

        load_truck();
        System.out.println(pack1 + "\n");
        System.out.println(pack2 + "\n");


    }

     if(pack1 == "pk1 On the truck" || pack2 == "pk2 On the truck") {

        drive_truck();
        System.out.println("Driving to the first place " + "\n");
        System.out.println("Driving to the second place " + "\n");


    }

     if (truckInUse == true) {

        unload_truck1();

        System.out.println("pk1 delivered in the " + place + "\n");

        unload_truck2();

        System.out.println("pk2 delivered in the " + place + "\n");
    }



}




public static void start() {

    city = "London";
    airport = "lhr";

    return;

}

public static void load_plane() {

    city = "London";
    pack1 = " pk1 On board";
    pack2 = " pk2 On board";

    return;
}

public static void fly() {

        city = "Paris";
        airport = "cdg";
        airplaneInUse = true;

    return;

}

public static void unload_plane() {

    pack1 = "Arrived in Paris";
    pack2 = "Arrived in Paris";
    airplaneInUse = false;

    return;

}


public static void load_truck() {

    pack1 = "pk1 On the truck";
    pack2 = "pk2 On the truck";

    return;

}


public static void drive_truck() {

    truckInUse = true;

    return;

}

public static void unload_truck1() {

    truckInUse = false;
    pack1 = "Arrived in South";
    place = "South";

    return;

}

public static void unload_truck2() {

    truckInUse = false;
    pack1 = "Arrived in North";
    place = "North";

    return;

}




}

我如何达到目标?如何获得组合计算来解决该问题?

1 个答案:

答案 0 :(得分:0)

我认为您正在错误地解决它。不要尝试实现任何if / else命令式逻辑。声明您的操作(也称为操作员),领域,问题,并致电计划者解决。如果您确实想创建域和问题而没有将其编码为PDDL并让计划程序(例如pddl4j)对其进行解析,则可以使用Java对其进行编码,并将其作为编码域和编码问题进行处理。

您的代码结构将与您放入PDDL中的代码结构非常相似,因此,除了节省解析时间并加快解决方案速度之外,我认为这样做没有什么意义。如果这样做,请继续阅读...

请参见一个代码示例,如何通过pddl4j API调用计划程序:https://github.com/pellierd/pddl4j/wiki/A-tutorial-to-develop-your-own-planner#step-6-searching-for-a-solution-plan

现在,通常,您将让PDDL解析器完成这项工作:https://github.com/pellierd/pddl4j/wiki/A-tutorial-to-develop-your-own-planner#step-5-parse-and-encode-the-pddl-domain-and-problem-files

...但是,如果要对其进行编码,则需要使用OpDomainProblem类声明操作,域和问题。

然后,您将 encode 称为问题,并按照教程之一(我上面粘贴的链接)中的说明在pddl4j中调用计划者之一。这有帮助吗?