Re: [computer-go] Go datastructures

2007-07-20 Thread Zach Wegner
When I started I used this as well. However when I realized how many times I would be looking at all adjacent intersections I switched to having an array adjacent[BOARD_SIZE * BOARD_SIZE][5]. In addition to making the code cleaner, this allows for more compact code size and (I think) more predicta

Re: [computer-go] Go datastructures

2007-07-20 Thread Darren Cook
> I don't use functions to convert 0-n to x, y. I use arrays of constants > instead. It's faster. APD.get_x(d), for instance, is doing a lookup in an array that is made by the constructor once when the program starts up. Everything is inline so it is the same. Darren __

RE: [computer-go] Go datastructures

2007-07-20 Thread David Fotland
On Behalf Of Darren Cook > Sent: Friday, July 20, 2007 5:17 PM > To: computer-go > Subject: Re: [computer-go] Go datastructures > > > > I always used a 1-dimensional 25x25 = 625 integer array with 0 for > > black 1 for white 2 for empty and 3 for border (everything els

Re: [computer-go] Go datastructures

2007-07-20 Thread David Doshay
When we deal with patterns and their rotations/reflections, we have a "canonical" version that contains everything we care about, and all of the R/R patterns have pointers to the canonical. If these are being generated by some automated algorithm, we generate all of the R/R as soon as we see the n

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Ian Osgood
On Jul 20, 2007, at 12:10 PM, Jason House wrote: That's essentially the best that I came up with. Since bit board operations on 19x19 are slow... They are not necessarily slower than on smaller boards if you store only non-zero portions of your bitmaps along with the start and end row

Re: [computer-go] Go datastructures

2007-07-20 Thread forrestc
>it > has functions to turn a 0..N coord into x and y coords, functions to > rotate points, functions to return the coord a certain distance away > (e.g. ikken to the North, keima to the South-East). Okay, I've got functions that detect a certain relation between stones--and can be linked together

Re: [computer-go] Go datastructures

2007-07-20 Thread Darren Cook
> I always used a 1-dimensional 25x25 = 625 integer array with 0 for > black 1 for white 2 for empty and 3 for border (everything else). > > This way I can have a 21x21 board with 2 rows of border cells > surrounding it. David Fotland, on the other hand, seems to use a 19x19 grid, and detect off

Re: [computer-go] Go datastructures

2007-07-20 Thread Ray Tayek
At 08:38 PM 7/19/2007, you wrote: In the engine I've been working on for a week or two (I'm brand new to computer-go) I use: typedef int INTERSECTION; typedef enum { BLACK, WHITE, EMPTY } COLOR; i used: typedef enum { BLACK, WHITE, EMPTY,OFFBOARD } COLOR; once. it eliminated tests for array bo

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread terry mcintyre
From: Ian Osgood <[EMAIL PROTECTED]> On Jul 20, 2007, at 2:25 PM, Andrés Domínguez wrote: > 2007/7/20, Ian Osgood <[EMAIL PROTECTED]>: >> >> My program disallows playing in eyes (string of empty surrounded >> by self) >> unless a neighboring stone is in atari. That catches your special- >> cas

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Ian Osgood
On Jul 20, 2007, at 2:25 PM, Andrés Domínguez wrote: 2007/7/20, Ian Osgood <[EMAIL PROTECTED]>: My program disallows playing in eyes (string of empty surrounded by self) unless a neighboring stone is in atari. That catches your special- case, but is not good for saving tails (strings conne

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Andrés Domínguez
2007/7/20, Ian Osgood <[EMAIL PROTECTED]>: > Looking at only the four neighbors to detect eye-like points seems like it could leave many false eyes and allow captures of dangling chains. Is there any mechanism to avoid this problem in the play of the bot? > > > It does also look at the diagonals

Re: [computer-go] Go datastructures

2007-07-20 Thread Ian Osgood
On Jul 20, 2007, at 10:58 AM, Jason House wrote: On 7/20/07, Ian Osgood <[EMAIL PROTECTED]> wrote: My beginner UCT program (http://www.quirkster.com/forth/fgp.html) uses bitboards because it is very simple to express the rules of Go using bit operations. However, a mailbox board which contains

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Jason House
On 7/20/07, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: Jason House said: > Thanks for the documentation. I have a few questions. > > Looking at only the four neighbors to detect eye-like points seems like > it could leave many false eyes and allow captures of dangling chains. > Is there any m

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread forrestc
Jason House said: > Thanks for the documentation. I have a few questions. > > Looking at only the four neighbors to detect eye-like points seems like > it could leave many false eyes and allow captures of dangling chains. > Is there any mechanism to avoid this problem in the play of the bot? Eye

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Ian Osgood
On Jul 20, 2007, at 8:04 AM, Jason House wrote: On 7/20/07, Peter Drake <[EMAIL PROTECTED]> wrote: On Jul 20, 2007, at 7:23 AM, Jason House wrote: Thanks for the documentation. I have a few questions. Looking at only the four neighbors to detect eye-like points seems like it could leave

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Peter Drake
It looks like you're right -- but I did say O (rather than THETA), so I'm also technically correct. :-) Peter Drake http://www.lclark.edu/~drake/ On Jul 20, 2007, at 9:15 AM, Richard J. Lorentz wrote: Peter Drake wrote: On Jul 20, 2007, at 8:04 AM, Jason House wrote: I thought he was usi

Re: [computer-go] Go datastructures

2007-07-20 Thread Jason House
On 7/20/07, Ian Osgood <[EMAIL PROTECTED]> wrote: My beginner UCT program (http://www.quirkster.com/forth/fgp.html) uses bitboards because it is very simple to express the rules of Go using bit operations. However, a mailbox board which contains references into string objects which incrementally

Re: [computer-go] Go datastructures

2007-07-20 Thread Ian Osgood
On Jul 19, 2007, at 8:16 PM, Joshua Shriver wrote: Greetings, What kind of data structures do you all use for your engines, in respect to board representation and move generation. I know in chess bitboard, mailbox board[8][8], 0x88 exist all with their pro's and cons. Are there similar concept

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Richard J. Lorentz
Peter Drake wrote: On Jul 20, 2007, at 8:04 AM, Jason House wrote: I thought he was using the disjoint set! I'll recheck. Well written disjoint sets average out to nearly O(1) operations for everything. Yes -- O(log* n) to be precise, ... At the risk of being accused of serious nit-picki

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Peter Drake
Yes: log* is to log what log is to division. In other words, it's the number of times you have to take a logarithm before you get down to 1. It's an extremely slowly-growing function. It's conceivable that actual, empirical time is a better metric than asymptotic time here, because we're no

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Jason House
On 7/20/07, Peter Drake <[EMAIL PROTECTED]> wrote: On Jul 20, 2007, at 8:04 AM, Jason House wrote: > I thought he was using the disjoint set! I'll recheck. Well > written disjoint sets average out to nearly O(1) operations for > everything. Yes -- O(log* n) to be precise, as mentioned in my

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Peter Drake
On Jul 20, 2007, at 8:04 AM, Jason House wrote: I thought he was using the disjoint set! I'll recheck. Well written disjoint sets average out to nearly O(1) operations for everything. Yes -- O(log* n) to be precise, as mentioned in my book, plug>Data Structures and Algorithms in Java. M

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Jason House
On 7/20/07, Peter Drake <[EMAIL PROTECTED]> wrote: On Jul 20, 2007, at 7:23 AM, Jason House wrote: Thanks for the documentation. I have a few questions. Looking at only the four neighbors to detect eye-like points seems like it could leave many false eyes and allow captures of dangling chains

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Peter Drake
On Jul 20, 2007, at 7:23 AM, Jason House wrote: Thanks for the documentation. I have a few questions. Looking at only the four neighbors to detect eye-like points seems like it could leave many false eyes and allow captures of dangling chains. Is there any mechanism to avoid this problem

Re: Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-20 Thread Jason House
Thanks for the documentation. I have a few questions. Looking at only the four neighbors to detect eye-like points seems like it could leave many false eyes and allow captures of dangling chains. Is there any mechanism to avoid this problem in the play of the bot? I'll have to think more about

Re: [computer-go] Go datastructures

2007-07-20 Thread Magnus Persson
Quoting Joshua Shriver <[EMAIL PROTECTED]>: What kind of data structures do you all use for your engines, in respect to board representation and move generation. I know in chess bitboard, mailbox board[8][8], 0x88 exist all with their pro's and cons. Are there similar concepts for Go? I always

Fast data structures explained! (was Re: [computer-go] Go datastructures)

2007-07-19 Thread Peter Drake
What a timely thread! I've reimplemented Łukasz Lew's libego in Java for the latest edition of Orego. It includes something of an explanation of the data structures. I believe the code itself is relatively clear. The goodies are here: http://www.lclark.edu/~drake/go/ Enjoy! Peter Drake h

Re: [computer-go] Go datastructures

2007-07-19 Thread Zach Wegner
In the engine I've been working on for a week or two (I'm brand new to computer-go) I use: typedef int INTERSECTION; typedef enum { BLACK, WHITE, EMPTY } COLOR; struct GROUP { INTERSECTION base; COLOR color; int count; int liberties; INTERSECTION children[5]; INTERSECTION parent;

Re: [computer-go] Go datastructures

2007-07-19 Thread Sanghyeon Seo
2007/7/20, Joshua Shriver <[EMAIL PROTECTED]>: What kind of data structures do you all use for your engines, in respect to board representation and move generation. I know in chess bitboard, mailbox board[8][8], 0x88 exist all with their pro's and cons. Are there similar concepts for Go? Below

[computer-go] Go datastructures

2007-07-19 Thread Joshua Shriver
Greetings, What kind of data structures do you all use for your engines, in respect to board representation and move generation. I know in chess bitboard, mailbox board[8][8], 0x88 exist all with their pro's and cons. Are there similar concepts for Go? -Josh _