Selection to book

You can copy games into an openings book to extend it. You can drag & drop another database symbol onto the book symbol, or drag & drop a selection of games list or opening keys onto it.

Click "Selection to Book" to generate a book on-the-fly

The book is being built...

This is what the book window displays:

• N: Number of games. At the top you see the total number of games which led to the current board position. In the column itself you see the number of games in which each move was executed.
• %: The percentage score achieved by the move is always given from the point of view of the colour to play. If the number of games is low then the percentage is given in grey because it does not have great statistical significance.
• Av: The Elo average of the players who used the move. If only a small percentage of the players had a rating then the number is given in grey.
• Perf : The Elo performance of the move is the rating a player would have achieved in a fictitious tournament playing the move in all his games.
• Statistics: For any highlighted move the program displays at the bottom the exact number of games that were won, drawn or lost. The bar graphics on the left make it easy to take in the information at a glance. On the right you can see the total number of games in which the move was made, plus the average ratings of the players.