I'm trying to solve a Pacman-styled PDDL problem and there's a particular scenario I've been stuck on for days now. I'm getting the classic
ff: goal can be simplified to FALSE. No plan will solve it
which means the issue is trivial and logic related. However, I'm new to PDDL and can't seem to figure out what's causing it.
The problem is simple, Pacman (P) has to eat the Food (F), but two ghost agents (G) are blocking it. To get past them, Pacman needs to consume the Capsule (C), making him invisible.
(Edit: I've deleted the question as it was part of an assignment. I managed to solve the issue and will post the solution as soon as the assignment is graded.)
In this thread: About PDDL in AI planning #haz mentioned a good methodology to debug your PDDL Model when the goail is unreachable from the initial state.
The best way to test this out is to follow the following strategy: (1) write down a plan you know will solve it; (2) starting with the first action, set the goal to the precondition; (3) repeat to the end. If that fails, start changing the initial state to what you expect the complete state to be during the execution of the plan. – haz May 1 at 2:04
I uploaded a new version which is able to find a solution (if Ghosts are not in the path of foods):
http://editor.planning.domains/#read_session=c7Vez9nrti
Two main issues:
you never delete GhostPos, but it appears in the goal formula
If GhostPos is on the way to a FoodPos, then you can never reach the food as the move action requires not to be a Ghost.
Related
I'm using Optaplanner to automatically solve school timetables. After a timetable has been solved the user will manually change some lessons and will get feedback on how this affects the score via the following call:
scoreManager.updateScore(timetable);
This call takes some 200ms and will, I assume, do a complete evaluation. Im trying to optimize this and want to only pass in a Move object so that Optaplanner only has to recalculate the delta, like:
scoreManager.updateScore(previousTimetable,changeMove);
Is there a way to do this?
There really is no way how to do just a single move. You don't do moves - the solver does moves. You can only make external problem changes to the solution. You should look into the ProblemChange interface and its use in the SolverManager.
However, the problem change will likely reset the entire working solution anyway. And after the external change is done, you're not guaranteed that the solution will still make sense. (What if it breaks hard constraints now?) You simply need to expect and account for the fact that, after users submit their changes, the solver will need to run; possibly even for a prolonged period of time.
I have been working on a simple game in Unreal Engine 4. I am trying to make it so when a player is hit by a cube they take damage. However, I am stuck on creating a condition. I have previously used:
to set up a condition where a player only takes damage if they are touched by the cube (In my cube pawn blueprints).
This doesn't work however - when trying to set-up my health bar:
This shows that I am now using entirely new variables to attempt to get a successful updating bar.
Without setting it up so when a cube hits the player, the player takes damage, the player will take damage from simply jumping at walking into other surfaces.
I have created a function that successfully updates my current health and max health so I don't need to show, or need help with the maths or updating the widget. Is there a way for me to use the branch to create an if statement that checks the contact is form a cube?
I am quite new to blueprints and have mostly developed through the use of tutorials. If you need clarity on my question or you don't understand what I am asking please leave a comment and I will try to update. I have looked long and hard for an answer, but I have found that Unreal Engine 4 hasn't got many questions that I can tailor the answer to my situation. If the answer is already in another post on this website, comment saying so and I will remove this post.
Thanks for any help you can give me :)
(This also has a itch.io page for me to quickly share to my friends so I will also credit the person who helped me there)
If I've understood your question correctly, I believe you are just asking how to check if the cube has hit the player character and not some other actor.
Instead of using an if statement as you suggested, you can just cast the Other Actor property to your first person character. If the cast is successful then it hit the character, if the cast fails, it hit something else. You can then call the damage function which you said you've already created. Below is a basic example you could use in your cube blueprint. You will also need to make sure you have a collision box surrounding your cube mesh (and your character, but I can already see that in your screenshot).
Let's assume you have a pipeline with steps that can fail for some input elements for example:
FetchSomeImagesFromIds -> Resize -> DoSomethingElse
In this case the 1st step downloads 10 out of a 100 images... and passes those to resize..
I'm looking for suggestions on how to report or handle this missing data at the pipeline level for example something like:
Pipeline.errors() -> PluginX: Succeed: 10, Failed: 90, Total: 100, Errors: key: error
My current implementation removes the missing keys from current_keys so that the key -> data mapping is kept and actually exits the whole program if there's anything missing.. given the previous problem with https://github.com/Neuraxio/Neuraxle/issues/418
Thoughts?
I think that using a Service in your pipeline would be the good way. Here's what I'd do if I think about it, although more solutions could exist:
Create your pipeline and pipeline steps.
Create a context and add to the context a custom memory bank service in which you can keep track of what data processed properly or not properly. Depending on your needs and broader context, it could be either a positive data bank, or negative one, in which you'd respectively either add the processed examples or substract them from the set.
Adapt the pipeline made at point 1, and its steps, such that it can use the service from the context in the handle_transform_data_container methods. You could even have a WhileTrue() step which would loop forever until a BreakIf() step would evaluate that everything has been processed for instance, if you want your pipeline to work until everything has been processed, and fetching the batches as they come without an end condition other than the BreakIf step and its lambda. The lambda would call the service indeed to know where the data processing is at.
At the end of the whole processing, wheter you breaked prematurely (without any while loop) or wheter you did break only at the end, you still have access to the context and to what's stored inside.
More info:
To see an example on how to use the service and context together and using this in steps, see this answer: https://stackoverflow.com/a/64850395/2476920
Also note that the BreakIf and While steps are core steps that are not yet developed in Neuraxle. We've recently had a brilliant ideas with Vincent Antaki where Neuraxle is a language, and therefore steps in a pipeline are like basic language keywords (While, Break, Continue, ForEach) and so forth. This abstraction is powerful in the sense that it's possible to control a data flow as a logical execution flow.
This is my best solution for now and this exactly has never been done yet. There may be much more other ways to do this, with creativity. One could even think of doing TryCatch steps in the pipeline to catch some errors and managing what happens in the execution flow of the data.
All of this is to be done in Neuraxle and is not yet done. We're looking for collaborators. That would do a nice paper as well: "Machine Learning Pipelines as a Programming Language" :)
I'm building a student schedule generator and I need a way of producing more than one solution. Is there some way to save off feasible scores or scores of Xhard/Ysoft?
I need to be able to output more than one potential schedule, that way the student will have a choice for one schedule over the other if for whatever reason they don't want the "best" schedule (maybe they don't like one of the professors, maybe they don't want an 8am class, whatever)
My original idea was to save off all feasible solutions using the bestSolutionChanged event listener. The problem with this, is that once it finds a 0hard/0soft score, it ignores all scores after that, including scores that are equal.
Ideally I'd like to save off all scores of 0hard/-3soft or better, but just being able to save any feasible scores or force optaplanner to look for a new best score would be useful as well.
This is not a solution, but an analysis of the problem:
Hacking the BestSolutionRecaller is obviously not just a big pain, it's also behaviour we don't want to encourage as it makes upgrading to newer version an even bigger pain. So don't expect us to solve this by adding an easy way to configure that in the solver config any time soon. That being said, a solution for this common problem is clearly needed.
When a new best solution is found, it is planning cloned (see docs for definition) from the working solution (the internal solution in OptaPlanner). This allow us to remember that new best solution as the working solution solution changes. That also means the BestSolutionChangedEvents gets a plannng clone and can safely ship it to another thread, for example to marshal it to a client (presuming any ProblemFactChanges you create do copies instead of alterations), without being corrupted by the solver thread that modifies the working solution.
New best solution imply that workingScore > bestScore. The moment it instead does workingScore >= bestScore, we need far more planning clones (which are a bit CPU expensive), but we could then just send out BestSolutionChangedEvents for that too, if and only if a flag is enabled of course, because most users (unlike yourself) don't want this behaviour.
One proposal is to create a separate BestSolutionChangedOrSameEvent, next to the BestSolutionChangedEvent. This might not be ideal, because we need to be able to detect whether or not someone needs those extra planning clones.
Another proposal is to just have a flag in the <solver> config that switches from > to >= behavior for BestSolutionChangedEvent.
Please create a jira (see "get help" on webpage) and link it it here, or create a support ticket (also see "get help" on webpage).
I have a requirement for which I want to trigger an action (like calling a REST-ful service) in the event a keyword is found in the logs. The trigger would have to be fairly real time. I was evaluating open source solutions like GrayLog2, ELK stack (which I believe can't analyse real time), fluentd etc. but wanted to know your opinion on that. It would be great if the tool also allows setting up rules against key words to eliminate false positives and easy to set up.
I hope this makes sense and apologies if this has been discussed elsewhere!
You can try Massalyzer. It's a real-time analyzer too, very fast (up to 10 millinon line per sec), and you can analyze unlimited size with free demo version.
So, I tried Logstash+Graylog2 combination for the scenario I described in the question and it works quite well. I had to tweak a few things to make Logstash work with Graylog2, especially around capturing the right log levels. I will try this out on a highly loaded clustered environment and update my findings here.