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I am looking for any direction on how to implement the process below, you should not need to understand much at all about poker.
Below is a grid of possible two-card combinations.
Pocket pairs in blue, suited cards in yellow and off-suited in red.
Essentially there is a slider under the matrix which selects a percentage of possible combinations of two cards which a player could be dealt. However, you can see that it moves in a sort of linear fashion, towards the "better" cards.
These selections are also able to be parsed from strings e.g AA-88,AKo-AJo,KQo,AKs-AJs,KQs,QJs,JTs is 8.6% of the matrix.
I've looked around but cannot find questions about the specific selection process. I am not looking for "how to create this grid" or , more like how would I go about the selection process based on the sliding percentage. I am primarily a JavaScript developer but snippets in any language are appreciated, if applicable.
My initial assumptions are that there is some sort of weighting involved i.e. (favoured towards pairs over suited and suited over non-suited) or could it just be predetermined and I'm overthinking this?
In my opinion there should be something along the lines of "grouping(s)" AND "a subsequent weighting" process. It should also be customisable for the user to provide an optimal experience (imo).
For example, if you look at the below:
https://en.wikipedia.org/wiki/Texas_hold_%27em_starting_hands#Sklansky_hand_groups
These are/were standard hand rankings created back in the 1970s/1980s however since then, hand selection has become much more complicated. These kind of groupings have changed a lot in 30 years so poker players will want a custom user experience here.
But lets take a basic preflop scenario.
Combinations:- pairs = 6, suited = 4, nonsuited = 12
1 (AA:6, KK:6, QQ:6, JJ:6, AKs:4) = 28combos
2 (AQs:4, TT:6, AK:16, AJs:4, KQs:4, 99:6) = 40
3 (ATs:4, AQ:16, KJs:4, 88:6, KTs:4, QJs:4) = 38
....
9 (87s:4, QT:12, Q8s:4, 44:6, A9:16, J8s:4, 76s:4, JT:16) = 66
Say for instance we only reraise the top 28/1326 of combinations (in theory there should be some deduction here but for simplicity let's ignore that). We are only 3betting or reraising a very very obvious and small percentage of hands, our holdings are obvious at around 2-4% of total hands. So a player may want to disguise their reraise or 3bet range with say 50% of the weakest hands from group 9. As a basic example.
Different decision trees and game theory can be used with "range building" so a simple ordered list may not be suitable for what you're trying to achieve. depends on your programs purpose.
That said, if you just looking to build an ordered list then you could just take X% of hands that players open with, say average is 27% and run a hand equity calculator simulation tweaking the below GitHub to get different hand rankings. https://github.com/andrewprock/pokerstove
Theres also some lists here at the bottom this page.
http://www.propokertools.com/help/simulator_docs
Be lucky!
I've been looking into the k nearest neighbors algorithm as I might be developing an application that matches fighters (boxers) in the near future.
The reason for my question, is to figure out which would be the best approach/algorithm to use when matching fighters based on multiple parameters and constraints depending on the rule-set.
The relevant properties of each fighter are the following:
Age (Fighters will be assigned to an agegroup (15, 17, 19, elite)
Weight
Amount of fights
Now there are some rulesets for what can be allowed when matching fighters:
A maximum of 2 years in between the fighters (unless it's elite)
A maximum of 3 kilo's difference in weight
Now obviously the perfect match, would be one where all the attendees gets matched with another boxer that fits within the ruleset.
And the main priority is to match as many fighters with each other as possible.
Is K-nn the way to go or is there a better approach?
If so which?
This is too long for a comment.
For best results with K-nn, I would suggest principal components. These allow you to use many more dimensions and do a pretty good job of spreading the data through the space, to get a good neighborhood.
As for incorporating existing rules, you have two choices. Probably, the best way is to build it into you distance function. Alternatively, you can take a large neighborhood and build it into the combination function.
I would go with k-Nearest Neighbor search. Since your dataset is in a low dimensional space (i.e. 3), I would use CGAL, in order to perform the task.
Now, the only thing you have to do, is to create a distance function like this:
float boxers_dist(Boxer a, Boxer b) {
if(abs(a.year - b.year) > 2 || abs(a.weight - b.weight) > e)
return inf;
// think how you should use the 3 dimensions you have, to compute distance
}
And you are done...now go fight!
Here is the facts first.
In the game of bridge there are 4
players named North, South, East and
West.
All 52 cards are dealt with 13 cards
to each player.
There is a Honour counting systems.
Ace=4 points, King=3 points, Queen=2
points and Jack=1 point.
I'm creating a "Card dealer" with constraints where for example you might say that the hand dealt to north has to have exactly 5 spades and between 13 to 16 Honour counting points, the rest of the hands are random.
How do I accomplish this without affecting the "randomness" in the best way and also having effective code?
I'm coding in C# and .Net but some idea in Pseudo code would be nice!
Since somebody already mentioned my Deal 3.1, I'd like to point out some of the optimizations I made in that code.
First of all, to get the most flexibly constraints, I wanted to add a complete programming language to my dealer, so you could generate whole libraries of constraints with different types of evaluators and rules. I used Tcl for that language, because I was already learning it for work, and, in 1994 when Deal 0.0 was released, Tcl was the easiest language to embed inside a C application.
Second, I needed the constraint language to run fairly fast. The constraints are running deep inside the loop. Quite a lot of code in my dealer is little optimizations with lookup tables and the like.
One of the most surprising and simple optimizations was to not deal cards to a seat until a constraint is checked on that seat. For example, if you want north to match constraint A and south to match constraint B, and your constraint code is:
match constraint A to north
match constraint B to south
Then only when you get to the first line do you fill out the north hand. If it fails, you reject the complete deal. If it passes, next fill out the south hand and check its constraint. If it fails, throw out the entire deal. Otherwise, finish the deal and accept it.
I found this optimization when doing some profiling and noticing that most of the time was spent in the random number generator.
There is one fancy optimization, which can work in some instances, call "smart stacking."
deal::input smartstack south balanced hcp 20 21
This generates a "factory" for the south hand which takes some time to build but which can then very quickly fill out the one hand to match this criteria. Smart stacking can only be applied to one hand per deal at a time, because of conditional probability problems. [*]
Smart stacking takes a "shape class" - in this case, "balanced," a "holding evaluator", in this case, "hcp", and a range of values for the holding evaluator. A "holding evaluator" is any evaluator which is applied to each suit and then totaled, so hcp, controls, losers, and hcp_plus_shape, etc. are all holding evalators.
For smartstacking to be effective, the holding evaluator needs to take a fairly limited set of values. How does smart stacking work? That might be a bit more than I have time to post here, but it's basically a huge set of tables.
One last comment: If you really only want this program for bidding practice, and not for simulations, a lot of these optimizations are probably unnecessary. That's because the very nature of practicing makes it unworthy of the time to practice bids that are extremely rare. So if you have a condition which only comes up once in a billion deals, you really might not want to worry about it. :)
[Edit: Add smart stacking details.]
Okay, there are exactly 8192=2^13 possible holdings in a suit. Group them by length and honor count:
Holdings(length,points) = { set of holdings with this length and honor count }
So
Holdings(3,7) = {AK2, AK3,...,AKT,AQJ}
and let
h(length,points) = |Holdings(length,points)|
Now list all shapes that match your shape condition (spades=5):
5-8-0-0
5-7-1-0
5-7-0-1
...
5-0-0-8
Note that the collection of all possible hand shapes has size 560, so this list is not huge.
For each shape, list the ways you can get the total honor points you are looking for by listing the honor points per suit. For example,
Shape Points per suit
5-4-4-0 10-3-0-0
5-4-4-0 10-2-1-0
5-4-4-0 10-1-2-0
5-4-4-0 10-0-3-0
5-4-4-0 9-4-0-0
...
Using our sets Holdings(length,points), we can compute the number of ways to get each of these rows.
For example, for the row 5-4-4-0 10-3-0-0, you'd have:
h(5,10)*h(4,3)*h(4,0)*h(0,0)
So, pick one of these rows at random, with relative probability based on the count, and then, for each suit, choose a holding at random from the correct Holdings() set.
Obviously, the wider the range of hand shapes and points, the more rows you will need to pre-compute. A little more code, you can still do this with some cards pre-determined - if you know where the ace of spades or west's whole hand or whatever.
[*] In theory, you can solve these conditional probability issues for smart stacking with multiple hands, but the solution to the problem would make it effective only for extremely rare types of deals. That's because the number of rows in the factory's table is roughly the product of the number of rows for stacking one hand times the number of rows for stacking the other hand. Also, the h() table has to be keyed on the number of ways of dividing the n cards amongst hand 1, hand 2, and other hands, which changes the number of values from roughly 2^13 to 3^13 possible values, which is about two orders of magnitude bigger.
Since the numbers are quite small here, you could just take the heuristic approach: Randomly deal your cards, evaluate the constraints and just deal again if they are not met.
Depending on how fast your computer is, it might be enough to do this:
Repeat:
do a random deal
Until the board meets all the constraints
As with all performance questions, the thing to do is try it and see!
edit I tried it and saw:
done 1000000 hands in 12914 ms, 4424 ok
This is without giving any thought to optimisation - and it produces 342 hands per second meeting your criteria of "North has 5 spades and 13-16 honour points". I don't know the details of your application but it seems to me that this might be enough.
I would go for this flow, which I think does not affect the randomness (other than by pruning solutions that do not meet constraints):
List in your program all possible combinations of "valued" cards whose total Honour points count is between 13 and 16. Then pick randomly one of these combinations, removing the cards from a fresh deck.
Count how many spades you already have among the valued cards, and pick randomly among the remaining spades of the deck until you meet the count.
Now pick from the deck as much non-spades, non-valued cards as you need to complete the hand.
Finally pick the other hands among the remaining cards.
You can write a program that generates the combinations of my first point, or simply hardcode them while accounting for color symmetries to reduce the number of lines of code :)
Since you want to practise bidding, I guess you will likely be having various forms of constraints (and not just 1S opening, as I guess for this current problem) coming up in the future. Trying to come up with the optimal hand generation tailored to the constraints could be a huge time sink and not really worth the effort.
I would suggest you use rejection sampling: Generate a random deal (without any constraints) and test if it satisfies your constraints.
In order to make this feasible, I suggest you concentrate on making the random deal generation (without any constraints) as fast as you can.
To do this, map each hand to a 12byte integer (the total number of bridge hands fits in 12 bytes). Generating a random 12 byte integer can be done in just 3, 4 byte random number calls, of course since the number of hands is not exactly fitting in 12 bytes, you might have a bit of processing to do here, but I expect it won't be too much.
Richard Pavlicek has an excellent page (with algorithms) to map a deal to a number and back.
See here: http://www.rpbridge.net/7z68.htm
I would also suggest you look at the existing bridge hand dealing software (like Deal 3.1, which is freely available) too. Deal 3.1 also supports doing double dummy analysis. Perhaps you could make it work for you without having to roll one of your own.
Hope that helps.
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StackOverflow crowd. I have a very open-ended software design question.
I've been looking for an elagant solution to this for a while and I was wondering if anyone here had some brilliant insight into the problem. Consider this to be like a data structures puzzle.
What I am trying to do is to create a unit converter that is capable of converting from any unit to any unit. Assume that the lexing and parsing is already done. A few simple examples:
Convert("days","hours") // Yields 24
Convert("revolutions", "degrees") // Yields 360
To make things a little more complicated, it must smoothly handle ambiguities between inputs:
Convert("minutes","hours") // Yields (1/60)
Convert("minutes","revolutions") // Yields (1/21600)
To make things even more fun, it must handle complex units without needing to enumerate all possibilities:
Convert("meters/second","kilometers/hour")
Convert("miles/hour","knots")
Convert("Newton meters","foot pounds")
Convert("Acre feet","meters^3")
There's no right or wrong answer, I'm looking for ideas on how to accomplish this. There's always a brute force solution, but I want something elegant that is simple and scalable.
I would start with a hashtable (or persisted lookup table - your choice how you implement) that carries unit conversions between as many pairs as you care to put in. If you put in every possible pair, then this is your brute force approach.
If you have only partial pairs, you can then do a search across the pairs you do have to find a combination. For example, let's say I have these two entries in my hashtable:
Feet|Inches|1/12
Inches|Centimeters|2.54
Now if I want to convert feet to centimeters, I have a simple graph search: vertices are Feet, Inches, and Centimeters, and edges are the 1/12 and 2.54 conversion factors. The solution in this case is the two edges 1/12, 2.54 (combined via multiplication, of course). You can get fancier with the graph parameters if you want to.
Another approach might be applying abductive reasoning - look into AI texts about algebraic problem solvers for this...
Edit: Addressing Compound Units
Simplified problem: convert "Acres" to "Meters^2"
In this case, the keys are understanding that we are talking about units of length, so why don't we insert a new column into the table for unit type, which can be "length" or "area". This will help performance even in the earlier cases as it gives you an easy column to pare down your search space.
Now the trick is to understand that length^2 = area. Why not add another lookup that stores this metadata:
Area|Length|Length|*
We couple this with the primary units table:
Meters|Feet|3.28|Length
Acres|Feet^2|43560|Area
So the algorithm goes:
Solution is m^2, which is m * m, which is a length * length.
Input is acres, which is an area.
Search the meta table for m, and find the length * length mapping. Note that in more complex examples there may be more than one valid mapping.
Append to the solution a conversion Acres->Feet^2.
Perform the original graph search for Feet->M.
Note that:
The algorithm won't know whether to use area or length as the basic domain in which to work. You can provide it hints, or let it search both spaces.
The meta table gets a little brute-force-ish.
The meta table will need to get smarter if you start mixing types (e.g. Resistance = Voltage / Current) or doing something really ugly and mixing unit systems (e.g. a FooArea = Meters * Feet).
Whatever structure you choose, and your choice may well be directed by your preferred implementation (OO ? functional ? DBMS table ?) I think you need to identify the structure of units themselves.
For example a measurement of 1000km/hr has several components:
a scalar magnitude, 1000;
a prefix, in this case kilo; and
a dimension, in this case L.T^(-1), that is, length divided by time.
Your modelling of measurements with units needs to capture at least this complexity.
As has already been suggested, you should establish what the base set of units you are going to use are, and the SI base units immediately suggest themselves. Your data structure(s) for modelling units would then be defined in terms of those base units. You might therefore define a table (thinking RDBMS here, but easily translatable into your preferred implementation) with entries such as:
unit name dimension conversion to base
foot Length 0.3048
gallon(UK) Length^3 4.546092 x 10^(-3)
kilowatt-hour Mass.Length^2.Time^(-2) 3.6 x 10^6
and so forth. You'll also need a table to translate prefixes (kilo-, nano-, mega-, mibi- etc) into multiplying factors, and a table of base units for each of the dimensions (ie meter is the base unit for Length, second for Time, etc). You'll also have to cope with units such as feet which are simply synonyms for other units.
The purpose of dimension is, of course, to ensure that your conversions and other operations (such as adding 2 feet to 3.5 metres) are commensurate.
And, for further reading, I suggest this book by Cardarelli.
EDIT in response to comments ...
I'm trying to veer away from suggesting (implementation-specific) solutions so I'll waffle a bit more. Compound units, such as kilowatt-hours, do pose a problem. One approach would be to tag measurements with multiple unit-expressions, such as kilowatt and hour, and a rule for combining them, in this case multiplication I could see this getting quite hairy quite quickly. It might be better to restrict the valid set of units to the most common ones in the domain of the application.
As to dealing with measurements in mixed units, well the purpose of defining the Dimension of a unit is to provide some means to ensure that only sensible operations can be applied to measurements-with-units. So, it's sensible to add two lengths (L+L) together, but not a length (L) and a volume (L^3). On the other hand it is sensible to divide a volume by a length (to get an area (L^2)). And it's kind of up to the application to determine if strange units such as kilowatt-hours per square metre are valid.
Finally, the book I link to does enumerate all the possibilities, I guess most sensible applications with units will implement only a selection.
I would start by choosing a standard unit for every quantity(eg. meters for length, newtons for force, etc) and then storing all the conversion factors to that unit in a table
then to go from days to hours, for example, you find the conversion factors for seconds per day and seconds per hour and divide them to find the answer.
for ambiguities, each unit could be associated with all the types of quantities it measures, and to determine which conversion to do, you would take the intersection of those two sets of types(and if you're left with 0 or more than one you would spit out an error)
I assume that you want to hold the data about conversion in some kind of triples (fstUnit, sndUnit, multiplier).
For single unit conversions:
Use some hash functions in O(1) to change the unit stucture to a number, and then put all multipliers in a matrix (you only have to remember the upper-right part, because the reflection is the same, but inversed).
For complex cases:
Example 1. m/s to km/h. You check (m,km) in the matrix, then the (s,h), then multiply the results.
Example 2. m^3 to km^3. You check (m,km) and take it to the third power.
Of course some errors, when types don't match like field and volume.
You can make a class for Units that takes the conversion factor and the exponents of all basic units (I'd suggest to use metric units for this, that makes your life easier). E.g. in Pseudo-Java:
public class Unit {
public Unit(double factor, int meterExp, int secondExp, int kilogrammExp ... [other base units]) {
...
}
}
//you need the speed in km/h (1 m/s is 3.6 km/h):
Unit kmPerH = new Unit(1 / 3.6, 1, -1, 0, ...)
I would have a table with these fields:
conversionID
fromUnit
toUnit
multiplier
and however many rows you need to store all the conversions you want to support
If you want to support a multi-step process (degrees F to C), you'd need a one-to-many relationship with the units table, say called conversionStep, with fields like
conversionID
sequence
operator
value
If you want to store one set of conversions but support multi-step conversions, like storing
Feet|Inches|1/12
Inches|Centimeters|2.54
and supporting converting from Feet to Centimeters, I would store a conversion plan in another table, like
conversionPlanID
startUnits
endUnits
via
your row would look like
1 | feet | centimeters | inches
I have to track if given a week full of data integers ( 40, 30, 25, 55, 5, 40, etc ) raise an alert when the deviation from the norm happens (the '5' in the above case). An extra nice thing to have would be to actually learn if 5 is a normal event for that day of the week.
Do you know an implementation in ruby that is meant for this issue? In case this is a classic problem, what's the name of the problem/algorithm?
It's a very easy thing to calculate, but you will need to tune one parameter. You want to know if any given value is X standard deviations from the mean. To figure this out, calculate the standard deviation (see Wikipedia), then compare each value's deviation abs(mean - value) from the mean to this value. If a value's deviation is say, more than two standard deviations from the mean, flag it.
Edit:
To track deviations by weekday, keep an array of integers, one for each day. Every time you encounter a deviation, increment that day's counter by one. You could also use doubles and instead maintain a percentage of deviations for that day (num_friday_deviations/num_fridays) for example.
This is often referred to as "anomaly detection" and there is a lot of work out there if you google for it. The paper Mining Deviants in Time Series Data Streams may help you with your specific needs.
From the abstract:
We present first-known algorithms for identifying deviants on massive data streams. Our algorithms monitor
streams using very small space (polylogarithmic in data
size) and are able to quickly find deviants at any instant,
as the data stream evolves over time.
http://en.wikipedia.org/wiki/Control_chart describes classical ways of doing this sort of thing. As Jonathan Feinberg commented, there are different approaches.
The name of the algorithm could be as simple as "calculate standard deviation."
http://en.wikipedia.org/wiki/Standard_deviation
However, any analysis you do should be specific to the data set. You should inspect historical data to get at the right algorithm. Standard deviation won't be a good measure at all unless your data is normally distributed. Your data might even be such that you just want to look for numbers above a certain max value... it really depends.
So, my advice to you is:
1) Google for statistics overview and read up on basic statistics.
2) Inspect any historical data you have.
3) Come up with some reasonable measure of an odd number.
4) Test your measure against your historical data and see if it highlights the numbers you think it should.
5) Repeat steps 2-4 as necessary to refine your algorithm.