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Subject: Re: Book design

Author: David Rasmussen

Date: 02:02:59 11/28/02

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On November 28, 2002 at 04:50:55, Sune Fischer wrote:

>I think that is more compact, but I don't get the transpositions. I'm not sure
>transposition are important anyway.

If you want to, you can do it like this. However, size is usually not a big
problem. I use a 128 bit structure as book entry. I don't actually use all 128
bits (yet), but it was easier to write, and book size is not a problem for me,
with hard disk sizes and prices these days.

Another thing that is important, is how to look up if a move is in the book.
Depending on the scheme, a large book can require linear search directly on the
disk, a quick binary search on disk, an even quicker indexing into a memory
block or something else. My first scheme was just linear on the disk. It was
simple to write, and it worked. As my book got larger, as 50-100 MB or more,
this became too slow, so I changed it to a binary search scheme, which is what I
use now. It is very fast, even with a large book. If I get into problems again,
I will make some sort of caching/indexing scheme in memory, so disk access is
minimized further.


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