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Book Tuning

For general Polyglot Book information, see Book Window.

Using Scid's Book Tuning feature, one can adjust the value associated with any move in an opening book. To navigate through the branches of the book one can just click on the line in the book tuning window or move around the game as usual. Adjusting a probability via the spinbox - the other values stay the same until being recalculated once Save is pressed.

Only integer values are shown - a zero may signify that this move has a probability of less than 1%, and most likely happens with books automatically generated from game collections. One should also note that all values should add up to 100%.

Adding Lines

Scid vs. PC includes Add Line and Remove Line features. The first will add all moves (or all White or Black moves) to the current position, the latter removes all moves from then current move till the game/var end.

Unlike adding and removing single moves , these line features ARE automatically saved to the book. And - due to implementation - they are not terribly optimal and may be slow with large books/move sequences.

Importing Books

The Import button imports a branch of the book, from the current position onwards, into a single game. (The continuation with the highest probability will make up the first variation , or main-line if adding on to the end of a game/variation). This allows to cherry-pick selected lines, and create a new book (exported from the PGN using the full version of polyglot).

Scid's default limit for importing books is 3000 moves. This value is assigned by ::book::exportMax , and can be altered from the console if desired (eg 'set ::book::exportMax 10000'), but doing so requires caution as higher limits are not properly tested (todo) and PGN limits may also apply. Books can consist of tens or hundreds of thousands of positions.

Moreover - in general it is not possible to import a whole book into a single game. Polyglot books are simply chess positions (and probabilities), with no requirement for them to be continuous or inclusive. Consider a book with entries for both White King and Queen-side castling. There is obviously no way to import both these positions into a single game. Additionaly - the number of book positions from any one position is not easy to discern (todo), though the total number of entries is it's size in bytes divided by 16.