Comments and Ratings

Great starting point for a hand evaluator however still has issues and does not rank all hands correctly. I discovered this several months ago but didn't want to bother with registering to post a reply. After a coworker mentioned using this evaluator to prove an argument, I mentioned the shortcomings. Unfortunately now I can't remember the cases it fails at, but I recall the error is due to the arbitrary method of ranking hands by hashing the card numbers. In some cases hands that should not have the same rank are hashed to the same value. A easy test is to use combs=nchoosek([1:52],5); ranks=rankp(combs,5); unique(ranks) and you will find that all possible hands gives 6987 possible ranks using rankp, which is incorrect, and instead you should get 7462.

Once the total ranks checks out, you should test and find that there are 10 straight flushes, 156 four of a kinds and full houses, 1277 flushes, 10 straights, 858 trips and two pairs, 2860 pairs, and 1277 high card ranks. Otherwise, there is still an error.

As an aside, the 2+2 evaluator can do unordered evaluations of 5-7 card hands, at blazing speeds, and can easily be ported to Matlab.

Thanks Tim C., there was a hole in the conditional statement for hands with pairs. Nice catch, the update has it fixed.

Great!

hi,
I was looking for a function which gives me the equity of two hands at a certain flop and two cards to come.
So i wrote a function which calls the rankp function 10000 times with a random turn and a random river and then looked which hand won how often. But the problem is when I ran rankp with a handlenght of five I always got an error saying:

Warning: Values other than 0 or 1 converted to logical 1
> In rankp>rankhand at 110
  In rankp at 71

Whats this error about? If I run it with a handlenght of two there is no problem at all.

Best regards
Daniel

Is this working properly??? In the example
change the last line of trick to

15 29 43 45 20 9 31
which is a K high straight....it returns a
ranking number greater (ie lower ranking value) than for the first line which is a pair of jacks???

Pretty neat, but it's a bit of shame that it uses toolboxes just to test for a straight. Couldn't the test:

(bweuler(rowsum(1:13))==1)

be replaced with something like

(sum(diff(rowsum(1:13))==-1)==1),

it's a bit unwieldy and not nearly as elegant as that in the code, but it seems to works. (Although I only tested it with two hands!)

Agreed Doug,

Also, I just spotted an error at my msg. The input should be:

{'A','spades' ; 2,'Diamonds'...}

forming a total of 7 rows and 2 columns.

Another idea, which is similar to the monte carlo simulation, is to use the code to play poker against matlab in a GUI environment.

You can also extend it by allowing to computer to make rational choices over the game considering probabilistic measures (maybe given by monte carlo?).

This is nice, but I think the input is not very intuitive, Why dont you make it as

[number,suite;number;suite ...]

e.g.

[A,Spades;2,Diamonds ...]

Also, another suggestion to make things interesting is to write functions and scripts for a monte carlo experiment and see how much % of the simulations you can beat with your current hand. Such function could take as input:

- number of players in the table
- you current hand

and the output would be the number of simulations where you beated the other players (or n of the others).

Then you can use the simulation function and play poker with your players assisted by Matlab power. Cool, isn't it?