ELECTRONIC T-NOTES


CHESSBASE USA'S WEEKLY ON-LINE NEWSLETTER


FOR THE WEEK OF AUGUST 4, 2002


FORCING FRITZ7 INTO AN OPENING -- PART TWO

by Steve Lopez

Last week we looked at two basic ways to force Fritz into a particular opening. This week we'll examine a more elaborate method: creating a new opening book on that specific opening. As always, this is not intended as a Windows primer; familiarity with basic Windows concepts and functions (folders, creating new files, etc.) is assumed.

The first step is to create a new (empty) opening book. In the main chessboard screen, go to the File menu and select "New", then "Openings book" from the submenu. This will display the standard Windows file select dialogue. Choose the folder in which you want the new book to be created (if you installed Fritz to the default folders, the default folder for a new opening book will be C:\My Documents\ChessBase\Books). You'll see *.ctg displayed in the "File name" field; you'll obviously want to change the asterisk to something more relevant and identifiable. For the examples in this article, I'll be creating a new book on the Ruy Lopez Steinitz Variation (which is wildly popular with online correspondence players for some weird reason). The ECO code for the Steinitz is C62, so I'll name the opening book C62.ctg.

Go to the Notation pane and click on the "Openings book" tab. Under the picture of a tree you'll see your filename displayed. You'll also see no moves in the tree (because we haven't added any yet -- that'll be our next step).

Open the database (game list) window (you can do this by clicking the button for it on the Toolbar, hitting F12 on your keyboard, or going to File/Open/Database). Your next step is to create a new database to hold the games that you want to transfer to the opening book. Go to File/New/Database and create a new database in a folder of your choice (the default is C:\My Documents\ChessBase\Database\Work). The default filename is New Database.cbh -- again, change "New database" to something more relevant. In my case, I created a new database called C62.cbh.

Go to the pulldown menu in the upper right of your screen. This menu is a list of the databases you've recently used. Select the database you want to perform a game search upon by clicking on it in this list (this will typically be your largest database); you'll see the list of games for that database appear. Find the games of the opening you want (by using the opening keys, doing a board position search for the defining position of the opening, or doing a straight ECO code search of the game headers). In my case, I do a header search for ECO code C62 by going to the Edit menu, selecting "Filter games", typing "C62" (without the quotes) in both "ECO" fields, placing a check in the "Game data" box, and clicking "OK". After a few moments, I'll see nothing but Steinitz Defense games displayed in the game list.

Next go to the Edit menu and click on "Select all". You'll see all of the games in the list become highlighted. Return to the Edit menu and select "Copy". After you do this, it will look like nothing happened. But what's just occurred is that you've told Fritz that you want to copy all of the highlighted games into another database.

Then return to the pulldown menu at the upper right of your screen and select the new database you created earlier. Instead of a list of games, you'll see the notation "No games found" appear in the main section of the screen -- this is because you haven't yet copied the games into it. To copy the games that you selected in the previous step, go to the Edit menu and select "Paste". You'll see a dialogue asking you to confirm the copy process; click "Yes" and the games will be copied into your new database. This will take a few moments -- the more games you're copying, the longer it will take (of course).

So we see that copying games in Fritz7 follows these steps:

  1. Highlighting the games you want to copy;
  2. Selecting "Copy" from the Edit menu (to identify these games to the program as the ones you want to copy);
  3. Opening the "target" database (the one into which you want the games to be copied);
  4. Selecting "Paste" from the Edit menu (to physically copy these games into the target database).

To merge these games into an opening book, first return to the main chessboard screen (click on the blue arrow button in the Toolbar to do this). Go to the Edit menu, select "Openings book", and then select the command "Import games" from the submenu. You'll get a dialogue that lets you identify the database that you want to import into the opening book; go to the folder you created it in and double-click on the database's name (in my case, I choose the C62.cbh database). You'll see a new dialogue that looks like this:

And now, friends, because I am terminally lazy, here's a repeat of this dialogue's description which I presented in a previous ETN (March 18, 2001 for those keeping score at home):

The "Games" fields are self-explanatory. In the graphic, the program will merge games 1 through 2797 (the whole database) into the tree. If, for some reason, you only want to merge a part of the database you can use these fields to configure what games will be merged into the tree.

"Length" requires a bit of explanation. A box allows you to type in the number of plies (half-moves) that will be merged into the tree. The default is "20", meaning that the lines of the opening book will be 20 plies (10 moves) long. This might be sufficient for some openings. Some heavily analyzed theoretical openings (such as the Ruy Lopez Zaitsev) might require a much higher value, such as 40.

"Absolute length" means that every variation imported into the tree will be the length you set in the box, regardless of whether it's a main line or an oddball branch variation. You'll typically use this for openings that cover a single ECO code.

"ECO relative length" means that frequently-played main lines will result in variations that are longer than the less-often played branch variations. With the ply value set for 30, the branch variations might be cut off after 8 or 9 moves while the main lines will be included out to move 15.

It's your choice, ultimately. If you're only interested in the tried and true theoretical lines, use the "ECO relative length" setting. If you want it all, no matter how odd, unsound, or poor the variation, use "Absolute length". My personal preference is to usually select "Absolute length". I frequently use these statistical trees in correspondence games; I find that my opponents often play sub-optimal opening moves. Having a larger, more inclusive tree lets me see these variations in action.

The final setting is "Include variations". If you have a lot of annotated games in your database, you'll have a lot of illustrative variations included by the annotators. These might be additional main line theory or they might be crappy little pitfalls and traps which are included to show ways in which a player can go wrong and how these errors can be punished. Checking this box includes the variations in the tree. Again, as a correspondence player, I live by these variations. I'm the "cheapo king" in correspondence chess -- I win about 25% of my games right in the opening, mainly due to these variations that I include in the trees I construct. Again, it's ultimately your choice.

Once you've made your selections, click "OK" and the program will go to work constructing a tree. The speed of the process depends on the number of games, whether or not you choose to allow variations, the depth you select for the tree, and the speed of your processor.

And once Fritz has finished merging the games into a tree, you have it -- you can force Fritz to play nothing but this particular opening (for either color) simply by loading this new opening book (File/Open/Openings book). And when you want to reload your previous opening book, all you need to is go to File/Open/Openings book, go to its folder, and select it. There's no limit (except hard drive space) to the number of opening books you can create -- just remember that you can load and use only one at a time.

If you want to delete the new database you created (as the intermediate step in the process of making the book), just load that database in the game list window, go to the Tools menu, select "Database", and then pick "Delete files" from the submenu.

There are some neat tricks you can do with opening books. One I like (and which was described in the Dark Ages of ETN -- back on September 14, 1997) is to create opening books for particular players. Instead of doing a search for a specific opening, you search for all the games of a particular player (playing either White or Black, not both) instead. For example, I can do a search for all of Alekhine's games as White, merge these into an opening book (calling it something like Alek_W.ctg, for example), load that book, and play a game against Fritz in which I have the Black pieces. What I'm doing is playing a game in which Fritz will use Alexander Alekhine's opening repertoire as White -- I'm (obviously) not playing against Alekhine, but I am doing the next best thing: playing against the openings he used when he was playing the White pieces.

Why not merge all of a player's games (as White and Black) into a single opening book? That's easy -- you'd have no way to know whether a particular move was played by the player or by one of his opponents. If you separate a player's games into two books (by color) you'll always know whether a given move was played by that player.

Although it seems like there are a lot of steps to creating specific opening books, it's really very easy. After you've done it a couple of times you'll see that it takes just a few minutes to create and assemble a new opening book.

Until next week, have fun!

You can e-mail me with your comments, suggestions, and analysis for Electronic T-Notes.