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Frequently Asked Questions

• What is Crafty's rating?
• How do I use Crafty?
• How do I make Crafty weaker?
• How do I make Crafty stronger?
• Can I save settings that I use all the time?
• How is Crafty's performance on the Macintosh compared to other platforms?

What is Crafty's rating?

There are several ways to answer this question:

1. Crafty's strength depends on the speed of the processor it's using, the size and content of its opening book, and the endgame tablebases that it's using.

2. Crafty isn't rated. You need to play in a few tournaments to get an official rating.

3. On ICC and FICS, Crafty has ratings around 2500-2700. However, these ratings are for fast time controls. These ratings cannot be translated to FIDE or UCSF ratings.

How do I use Crafty?

Type help for a list of Crafty's commands.

To quit Crafty, you can type end, quit, or q. You can also use the Quit command in the File menu or type Command-Q.

How do I make Crafty weaker?

Try the following commands:

book off

don't let it use the opening book, if any

ponder off

don't let it think while it's your turn

st 1

don't let it think for more than 1 second

hash 64K

make the hash table as small as possible

hashp 16

make the pawn hash table as small as possible

If you installed any endgame tablebases, move them somewhere else so Crafty can't find them. If Crafty is still too strong, try these commands:

sd n

don't let it think more than n moves ahead

extension check 0

turn off check extensions

extension recapture 0

turn off recapture extensions

extension 1reply 0

turn off one-reply extensions

null 0

turn off null-move pruning

How do I make Crafty stronger?

If you can beat Crafty, don't take moves back and don't play the same lines over and over. Otherwise, use Get Info to give Crafty as much memory as possible. Then try the following:

verbose 0

don't waste time printing anything

hash nK

make the hash table as large as possible

hashp n

make the pawn hash table as large as possible with the remaining memory

You should also install the largest opening book you can build and all the endgame tablebases you can fit on your disk. Finally, if you're using a 680x0 Macintosh, you should know that Crafty prefers a Power Macintosh. Crafty is much more efficient with a PowerPC processor.

Can I save settings that I use all the time?

Yes. You can put commands in a text file named "crafty.rc" and Crafty will execute them every time it starts up. The last command in this file must be exit. Here's an example:

hash 48M
hashp 4M
time 40/120/20/60
exit

How is Crafty's performance on the Macintosh compared to other platforms?

Although Crafty is a relatively strong Macintosh chess program, it could be performing much better. Crafty is essentially an elaborate 64-bit calculator. On other 32-bit platforms, 64-bit support is provided by the gcc compiler. On the Macintosh, 64-bit support is provided by a C++ class. The C++ class is much slower than gcc's built-in data type.

Better performance is a high priority. Currently, several compilers are being investigated as possible alternatives.

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