Manual de Chess Position Trainer 4 2012 | Page 61

Chess Position Trainer – © Stefan Renzewitz 2012 - all rights reserved

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In general the min-max-calculation works as follows: Let's say there are two candidate moves for a position:
Ne4 and Qg6. Now you know that Ne4 leads to a position +- and Qg6 to =. This means that the current position
is already +- as you can get into a variation which is evaluated as +- (assumption: all relevant candidate moves
are already covered). The whole trick is now that the program makes this decision for you and goes through
your whole opening backwards and while doing so it will update the position evaluations accordingly to the best
possible result the side to move can achieve.
The whole process is recursive and the program starts with your leaf nodes that means all end positions of your
repertoire where no further candidate moves exist are checked first and then going backwards through all variations up to the start position. In case all leaf nodes have an evaluation you will receive a fully evaluated opening
(every position will have an evaluation) even though you only entered this information for the leaf nodes (or
you used the EPD import/export function!). The program offers a function to jump to a leaf node which has not
yet an evaluation, but it will also import this key information if you have some good PGN files already.
Use the option to run the min-max-calculation based on computer evaluation if you imported an EPD file or in
case you used this field rather than the informator symbols.

4.5 Run Against Games
That’s probably one of the most powerful features which CPT offers. The typical situation: You play several
games over the internet or at a tournament. How can you find out what went wrong? Yes, you can use a chess
engine let it analyse it and finally let it show you what it would have played different. But if you entered already your whole repertoire, I bet you would like to know where you or your opponent played a so called “novelty”. That is, a move not covered by your repertoire. Your chess engine will show you moves which it questions and you played absolutely by intention, because they are part of your repertoire. Of course, from time to
time you have to check your lines again, but straighter forward is a different approach which CPT follows.
In a nutshell: This feature let you run any PGN games (for example your blitz games on an internet chess server) against your complete repertoire. It will show you then where you or your opponent played a move which is
not yet covered by your repertoire (it checks all your openings automatically!). Then you can easily analyse the