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Subject: Re: Book design

Author: Sune Fischer

Date: 02:13:56 11/28/02

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On November 28, 2002 at 05:02:59, David Rasmussen wrote:

>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.

Can you reveal a few details here :)
Binary search, how do I do that?



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