Posts made by Dash_Riprock

Hello people.  Sorry I haven’t checked back here in so long.
What with school and other projects, I don’t really have time to maintain this anymore with rule changes and such.  I would be happy to give someone the code if they wanted to give it a shot.

I have to warn you though, this app is not at all an easy one to maintain, for a few reasons:
1. Much of it is written like crap. I started the original version of this when I was pretty new to programming in general
2. No real documentation or comments at all.  What can I say, I never expected anyone other than me to be looking at it
3. The calculation algorithm is REALLY complicated.  I mainly wanted to to this for the challenge of it, but Monte Carlo methods (i.e. repeated dice rolling) are much more practical for this problem.  There are tons of unforeseen complications once you actually get into it.

@gamerman01:

Rip, this a very nice tool.
However, I’ve noticed that it’s not computing heavy bombers using 2 dice per bomber.  If I put in one heavy bomber attacking 2 units, there is a zero percent chance of both units being hit.  Do you guys use the house rule that you take the best of the 2 dice?  The default OOB rule is each heavy can get two hits because they roll 2 dice, and that’s the way most people play.  Any chance the tool can be updated for that?
I know you haven’t posted anything here for 6 months, but thought if I posted on your thread you might see it.
Thanks

should be fixed now

That bug should be fixed now.  I also made it so you can now use any number of defending fighters in a naval battle, since as someone pointed out the calc could be used half way into a battle once the carriers are already sunk.

Uhh sorry I haven’t been back here in a while, I’ll look into that bug and try to fix whatever other bugs people have been mentioning and post an updated version whenever I get a chance.

@Cmdr:

We need to clean up the code a bit, I think there’s a memory leak in the program. (If you have it on for a while, your computer slows down.)  Also, sometimes it won’t let you load fighters for your combat simulation (resetting them to zero).

It doesn’t let the defense in a naval battle have more fighters than it would be possible to fit on its carriers, if that’s what you mean.  As far as the memory leak, could you be more specific as to what you do when it happens, and what the memory/cpu usage are?  I tried keeping it open for various battles, and it stayed around 30MB mem usage and 0% cpu when idle.

If you see any other problems or lacking capability to run battles a certain way, feel free to give more input.  :-)

Thanks for all the positive input.  :-)
I’ve since updated it to fix a couple minor bugs, e.g. now only as many ships will bombard as there are units amphibiously attacking.

I’ve never played the game, but something that tends to help with older games is running in a compatibility mode.

Just right click the .exe > properties > Compatibility tab > run in compatibility mode check box > Windows 98 > OK

@Adlertag:

only whimps use odds calculators  :wink:

real men gamble  8-)

We mainly just use it after the game is over, so the losers can enter battles that were already played and complain about how unlucky they got.  :roll:

Well the group I play with recently bought the anniversary edition, and since no one else seems to have made one so far, I updated my calculator for the new rules like different unit values, bombardment not insta-kill, planes not hitting subs without destroyers present, ect.

You can get all the possible results by pressing the details button.  Just hold the mouse over to see what units are left for each outcome.
You will need Java installed to run it.  It should work on any OS.

http://www.filefactory.com/file/a0ha6c3/n/AAProbability_jar

edit 13 Oct.
New version - fixed bug with heavy bombers.  Also it should run slightly faster now

Sorry for the slow response, obviously I haven’t been on here in a while.

mshih:  You idea looks like it would work very efficiently, except that the order of loss is not determined.  Things like AA guns, subs only hitting ships, and in AA50 planes not hitting subs unless destroyers are present would make this extremely complicated.  It might still be possible to make a more efficient algorithm using a very complicated implementation of this, but I’m not going to be the one to do it.  :-)

It seems that the sharing site decided my file wasnt important enough.

In other news, I fixed  a small bug with how the AA worked.  I thought that the total number of hits was decided by the dice and then the attacker chose which of his planes he lost, but now I know that the dice gets rolled for each individual plane, which can make a slight difference in the odds.

Right, we essentially had most of the same ideas.  The choose function is the same thing as a given position on Pascal’s triangle. For efficiency, it pre-calculates the first 300 or so levels of Pascal’s triangle, as well as the first 300 powers of 1/6, 2/6, 3/6, 4/6, and 5/6 when the program is launched.

The thing that makes it really complicated is when you not only have multiple unit types but also subs involved, since you have to consider the number of normal hits, and for each one of those you also have to consider every possible number of naval-only hits for each side.

Well…  here it goes.
The basic idea is that it follows every possible path the battle can take, along with the chance that it will take each given path, until all the paths end, that is, one or both sides run out of units, or the number of rounds has reached the “hit and run” value. At this point the number of units for each player and the chance of arriving at that situation are stored for the result.  For a given situation, it has to figure out the chance that each side will hit every given possible number of times, e.g. the chance that 2 infantry and 1 armor will hit zero, one, two, or three times.  It then has to do the same thing for the defender, and then create every possible offshoot from the current situation.

For instance, a situation of 1 infantry on attack and one on defense will have 4 possible outcomes after one round of rolling:
attacker hits 0, defender hits 0
attacker hits 1, defender hits 0
attacker hits 0, defender hits 1
attacker hits 1, defender hits 1
The chance of, for example, the second one occurring is (1/6)*(2/3)*c, with c being the chance that this particular situation would arise in the first place.
In this situation, all possible outcomes will result in the battle being over, i.e. they wont have to create any new paths that have to be further calculated.

Of course, there is a problem: this will result in an infinite loop of each side missing forever, which is where some math comes in.  That possibility is ignored, and c has to be increased by the chance that both sides will miss, plus the chance that both sides will miss again, etc., forever. Conveniently, it works out that this particular infinite series just equals 1/(1-n), where n is the chance that both sides will completely miss.  In the 1 inf. vs. 1 inf. example this would mean that the first situation would never be calculated, and c would be multiplied by 1/(1-(5/6)(2/3)) = 2.25. None of this is necessary if “hit and run” is enabled, though, since the number of battles is limited anyway.

The way it calculates the probability of a given number x of units hitting is by using a formula (n choose k)p^k(1-p)^(n-k), where n is the number of events, k is the number that must be true, and p is the probability of each event being true.  It has to set up 5 different sets of events for the 5 different chances of a unit hitting, i.e. defending bombers or transports are in the first set of 1/6, while defending jet fighters are in the set of 5/6. It then has to use an algorithm to find every possible combination of x different hits, and add all the probabilities up.  In a battle with lots of attacking infantry and tanks, the chance that exactly two units hit is the chance that exactly 0 infantry and 2 tanks hit, plus the chance that 1 inf. and 1 tank hits, plus 0 inf. and 2 tanks.

The current product has a number of improvements over the original, most notably that it allows paths to re-converge and add their probabilities together rather than calculating the same parallel paths over and over again.

sits back in chair, panting

Boredom can do amazing things.
I finally made a “true” probability calculator.  It takes an exponentially longer time to run based on the number of units, but it is still very fast unless you try ridiculously massive battles, especially with lots of subs or an AA gun.
Making an algorithm to calculate the chance was surprisingly easy, but making it efficient enough to be practical was somewhat of a challenge.  :-)
You will also need Java.  And remember to click the “details” button.
http://www.filefactory.com/file/7236f2/n/AAProbability_jar

EDIT: I just fixed a bug and posted the fixed version. The old one had a problem with setting the unit loss order.

Im not really that interested in this anymore, but I could give you the source if you want and you can do whatever you want with it-I warn you though, it wasn’t exactly designed for anyone else to read.

BTW you know there are more options and results in separate windows right?

@Frood:

Does your sim handle submarines and abort conditions and such? I think those things really slow it down too.

Not that it matters, do you REALLY need to know to an accuracy of 1% or less?

Yes, it does, to the best of my understanding of the rules, and I think I have everything down right.  The only real problem it has that I know of is that the IPC lost details assume that units always die in the same order, so it just gives the results in numbers of units remaining, but in the case of AA guns and subs, this is not always the case.  I didnt think of that, though, until later and I dont feel like changing it now.  Not that its really a big deal, since it doesnt affect the actual chances.

As far as the accuracy thing, well, I didnt really think it was necessary either, but apparently some people want it REALLY accurate. :-)

I made a calculator in a non-internet based Java application that runs the simulation 1 mil, 4 mil, or 16 million times divided by the number of units in the battle, depending on the settings.  So, for instance, if you run a battle with 10 units on each side on high accuracy, it will run 800000 times in about 5 seconds, and come within 1/10th of a percent every time.  And Java is even considered slow compared to other languages like c++.

Your problem, Frood, is just that its going to run allot slower on an internet based program, unless there is some alternate language or method that works better. I guess it ends up being a trade-off between accuracy/time and convenience.

There, I re-hosted it.

Another related question: what if a plane which hasnt fought anything that turn flies over an enemy AA gun on its way to a different friendly territory?

I was bored, so I made (another) Revised probability calculator.  It includes research, unit priority settings, hit-and-run, and detailed result probabilities.  It runs the battle 1 million times/the number of units on low, 4 million on medium, and 16 million over the number of units on high. You will need Java installed.

http://files-upload.com/files/463773/AAProbability.jar

I have to give credit to frood for the detailed results part… admittedly mine is extremely similar  :-).
If anyone finds any glitches, please tell.