Creating a crazyhouse opening book for xboard

[hgm]

Are you sure these are Polygot books?

[Isaac]

Thank you Norbert. Actually what HGM suggested to me worked I think.

I think "xboard -ncp FILENAME" should indeed load the file automatically at startup. You should be able to see if you were successful in this by the Game List of all games in the file appearing in a separate window. If not, you can load the file interactively through the File -> Load Game menu.

Yeah the command that I ran works fine then. I can see my 600's games in a separated window.

How large the created bin book is will depend a lot on whether the games contain much overlap, or not. PGN is not a terribly compact format, so I am not sure if 512KB -> 33KB is anything to worry about. An empty book would be only 16 bytes, so there should be something in the bin book you made (about 2000 moves, actually).

To check if it all makes sense, you could open the Edit Book window, and see what it shows when you step through various opening positions.

Edit Book shows an empty window on the start position (which is not normal). When I let the engine play, it now play around 5 moves in a row out of the book, despite that "Edit Book" shows no move at all.

Note that only moves that were played a minimum number of times go into the book. I have forgotten what that number exactly was, but it is at least two. So the unique 'tail' of games would not be included in the book. If you don't want to exclude those, you must fool XBoard, by pressing 'Save Games to Book' a second time, with the same PGN still loaded. Each time you press it, it adds the currently loaded games to its internal buffer where it builds the book, before saving that. This way you can combine several PGNs into one book. But by this trick, you could make XBoard think every game was played twice, so that all their moves will be included in the book.

Ah!! That explains it! I've just tested to save the games twice in a row. Now my book.bin is over 500 kB so I am sure that all lines have been put into the book!!! Awesome...
Just to be sure of 2 things:
1)When saving the games to the book I chose the option "book strength 100" and "variety 0". I assume that this means that as white only 1-0 lines are saved and as black 0-1 lines, right?
2)In Common Engines I tick "use GUI book" and untick "Engine 1 has own book" and untick "Engine 2 has own book". Then I press on "Save settings". But every time I restart xboard, all settings are saved as I want except these ones. These 3 settings are all ticked so I must untick "Engine 1 has own book" and "Engine 2 has own book". Is this intended?

Anyway thank you very much, I'm pretty confident that I just built the book I had in mind!

[hgm]

Edit Book shows an empty window on the start position (which is not normal). When I let the engine play, it now play around 5 moves in a row out of the book, despite that "Edit Book" shows no move at all.

Are you sure XBoard was in variant crazyhouse when you did this? In variant normal you would not see any crazyhouse moves.

Just to be sure of 2 things:
1)When saving the games to the book I chose the option "book strength 100" and "variety 0". I assume that this means that as white only 1-0 lines are saved and as black 0-1 lines, right?

No, this setting is only used during probing. It adapts the book weights by raising them to a power. The book depth is also used during creation of the book, though.

2)In Common Engines I tick "use GUI book" and untick "Engine 1 has own book" and untick "Engine 2 has own book". Then I press on "Save settings". But every time I restart xboard, all settings are saved as I want except these ones. These 3 settings are all ticked so I must untick "Engine 1 has own book" and "Engine 2 has own book". Is this intended?

The "use GUI book" should be persistent. The other two are volatile options, though, meaning they are indeed not saved. This is because they are supposed to be engine--specific, and next time you might very well run with another engine. (This holds for all options that have a first/second version.) They are supposed to go on the engine line in the ini file (-firstXBook).

[Isaac]

Are you sure XBoard was in variant crazyhouse when you did this? In variant normal you would not see any crazyhouse moves.

No, I am not sure at all. I just started xboard with the "xboard" command without specifying the crazyhouse variant.

No, this setting is only used during probing. It adapts the book weights by raising them to a power. The book depth is also used during creation of the book, though.

Ah ok, good to know!

The "use GUI book" should be persistent. The other two are volatile options, though, meaning they are indeed not saved. This is because they are supposed to be engine--specific, and next time you might very well run with another engine. (This holds for all options that have a first/second version.) They are supposed to go on the engine line in the ini file (-firstXBook).

I see, thanks.