Re: [computer-go] Re: Euler numbers
At 10:19 AM 11/27/2007, you wrote: ... Back at my first computer job, where Steve Gray was a mentor, we had a special purpose computer called a BIP which did this quad counting as a basic operation. ... i also used to work with steve and dave. steve replied to a post i just sent him with: ... Euler number (an ambiguous designation, not recognized by most mathematicians) is easily calculated this way. Let Q1=the number of 2x2 neighborhoods with this configuration: X 0 0 1, and let Q3 be the number of these: X 1 1 0, where X is don't care. Then E=Q1-Q3. The Q's are counted with a raster sweep that moves across and down by one cell, so a given pixel is examined four times. Also E=B-H where B is the number of blobs (connected sets of 1's) and H is the number of holes (connected sets of 0's inside blobs). This formula for E does not treat the following patterns optimally, but it can be improved by making it slightly more complicated. 1 0 0 1 and 0 1 1 0. Holes on the edge can be counted by surrounding the image with a frame of 1's, but separate blobs touching the edge will become connected. It's been 36 years since I published this work (IEEE Trans. Computers, May 1971) so I may not recall everything perfectly. Incidentally, 2x2 neighborhoods are much better for tracing boundaries than 3x3, being faster and less ambiguous in crowded areas. I thought about the Go problem a little but never wrote any code. I'm not sure how much help the Euler number stuff would be. I got to be about low intermediate as a player. Steve Gray ... thanks --- vice-chair http://ocjug.org/ ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] euler numbers
On Nov 27, 2007 1:58 PM, Stuart A. Yeates [EMAIL PROTECTED] wrote: Could you give us a quick reference for exactly _which_ Euler numbers you're using? Wikipedia has three separate ones and the MathWorld site a similiar number. I cannot speak for Don, but in the work on solving Go I calculated the zeros-joined Euler number from independent bitmaps for Black and White with the border set to zero. IIRC half-joined and ones-joined performed worse (in the sense that the tree got bigger). An interesting alternative may be to combine colours so that the quad-counts directly use all the local information (that way, e.g., the diagonal miai-connection can be distinguished from one where the opponent is interfering). Back in 2002 I did not use this because the binary version has a smaller lookup table. The ICGA article contains a bit less information than my thesis. E.g., an explanation of the Euler numbers can be found on page 28 of the thesis. Here's a link: http://erikvanderwerf.tengen.nl/publications.html Erik On 26/11/2007, Don Dailey [EMAIL PROTECTED] wrote: After reading the paper on solving go on small boards, I am curious about the use of euler numbers as a simple evaluation element. I implemented a little euler number test program and it works correctly from a sample of about 50 positions of various types. I'm using the fast version where you scan 2 lines at a time with a lookup table. However, it calculates holes inside of groups and this does not detect eyes or holes on the edges of the board.It's not clear how to deal with this. I'm experimenting with a version that wraps a border around the whole board so that even the empty position looks like a 1 group with one big hole.This causes a lot of silly anomalies - for instance if you surround a big chunk of safe opponent stones it looks like a big hole.If you own half the board and the opponent owns the other half, his half contributes favorably to your euler number (it looks like a big hole of yours.) Of course I realize that this is just a quick and dirty calculation but I was curious about any tricks that others use to deal with it. - Don ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/ ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/ ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
[computer-go] New engine? From a Chess programmer perspective.
There was a thread on CCC (computer chess) about Go. An interesting post was made that linked to Leela, a Go engine and GUI written by the author of Deep Sjeng which is a moderate to high level chess engine. http://www.sjeng.org/leela.html Have any of you bought or tested the full version or have any more info? Seems interesting. -Josh ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] New engine? From a Chess programmer perspective.
On Dec 2, 2007 2:02 PM, Joshua Shriver [EMAIL PROTECTED] wrote: There was a thread on CCC (computer chess) about Go. An interesting post was made that linked to Leela, a Go engine and GUI written by the author of Deep Sjeng which is a moderate to high level chess engine. http://www.sjeng.org/leela.html Have any of you bought or tested the full version or have any more info? Seems interesting. I haven't seen Leela before, but the claim of high dan-level performance on 9x9 is certainly interesting. Do you have a link to the CCC thread? ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] New engine? From a Chess programmer perspective.
2007/12/2, Joshua Shriver [EMAIL PROTECTED]: There was a thread on CCC (computer chess) about Go. An interesting post was made that linked to Leela, a Go engine and GUI written by the author of Deep Sjeng which is a moderate to high level chess engine. http://www.sjeng.org/leela.html Have any of you bought or tested the full version or have any more info? In case anyone missed, Leela participated in 32nd KGS Computer Go Tournament. http://www.weddslist.com/kgs/past/32/index.html -- Seo Sanghyeon ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] New engine? From a Chess programmer perspective.
Sure, it's a long URL though. http://64.68.157.89/forum/viewtopic.php?t=17341postdays=0postorder=asctopic_view=start=30 -Josh On Dec 2, 2007 10:42 AM, Russell Wallace [EMAIL PROTECTED] wrote: On Dec 2, 2007 2:02 PM, Joshua Shriver [EMAIL PROTECTED] wrote: There was a thread on CCC (computer chess) about Go. An interesting post was made that linked to Leela, a Go engine and GUI written by the author of Deep Sjeng which is a moderate to high level chess engine. http://www.sjeng.org/leela.html Have any of you bought or tested the full version or have any more info? Seems interesting. I haven't seen Leela before, but the claim of high dan-level performance on 9x9 is certainly interesting. Do you have a link to the CCC thread? ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/ ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
[computer-go] Great day for CrazyStone!
According to computer-go.info, today CrazyStone won both sections of the KGS tournament (against strong opposition this month) and the UEC Cup in Japan. Well done, Rémi! ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
