mortimerp9 / prolog-graphplan Goto Github PK

Hello,

I have been downloading and trying your graphplan implementation with the rocket_plan example.
But unfortunately it returns thesame plan so many times. For instance test(P) returns the same plan about 20 times (or more):

?- test(P).
P = [[load(rocket1, london, a)], [move(rocket1, london, paris)], [unload(rocket1, paris, a)]] ;
P = [[load(rocket1, london, a)], [move(rocket1, london, paris)], [unload(rocket1, paris, a)]] ;
P = [[load(rocket1, london, a)], [move(rocket1, london, paris)], [unload(rocket1, paris, a)]] ;
P = [[load(rocket1, london, a)], [move(rocket1, london, paris)], [unload(rocket1, paris, a)]] ;
P = [[load(rocket1, london, a)], [move(rocket1, london, paris)], [unload(rocket1, paris, a)]] ;

I am using swipl Vesrion 7.2.3

Any idea what could cause this?

Thank you for your help

Fabrice

Hello, I'd like to solve a variant of your Rocket problem where:

• the rockets have a quantifiable amount of fuel (e.g. 1000 units)
• moving from a city to another one consumes some amount of fuel (e.g. 300 units).

In order to solve this, I thought I might add to the state a predicate: fuel(Rocket, FuelAmount).

But how can I update the state inside the adds predicate? I mean, can I somehow access the current state to read the FuelAmount of a Rocket in order to add fuel(Rocket, RemainingFuel) where RemainingFuel is FuelAmount - 300?

I'm sorry to trouble you but i'm unexperienced in Prolog and I can't tell if there's an obvious way solve this or if it's a limitation of Graphplan.