py2exe VS ChessPositionRanking

See this GitHub issue to follow the relevant discussion and development.

There are ways to bundle Python with your application using something like py2exe

Then you can turn the python program to an actual executable, a normal .exe file that user just launches and uses. If you chose to use this way, look into PyInstaller or py2exe. The executables will be obviously bigger, I think at least PyInstaller pretty much just packages Python and your script into .exe to make it work, so every program would be quite big (as each program has its own Python packaged). I also heard the process of turning the scripts to .exe is sometimes a bit problematic if you use some fancy imports and you also might run into problems with architecture.

*fyi, you can use a tool like py2exe or PyInstaller to convert Python scripts into a Windows Executable.

py2exe

3. There's extra nuanced things you might want to handle in the coding, like that pawns can't be on their own back row. That is significantly harder.

It looks to me like https://github.com/tromp/ChessPositionRanking has resolved these sorts of issues, but I haven't dug into exactly how.

Multinomial rankings can be combined with a dozen others to rank a subset of all chess positions including all legal ones. This allows one to sample millions of random such positions, determine how many are legal, and thus obtain an accurate estimate of 4.8&10^44 legal chess positions [2].

[1] https://github.com/tromp/ChessPositionRanking/blob/main/src/...

[2] https://github.com/tromp/ChessPositionRanking

The key words being "without promotion". Both bounds, this one and Steinerberger's, only consider positions reachable without promotion. Allowing promotions, one estimate suggests that the number is close to 4.82 × 10^44.

source

This one as well as Shannon number wiki seem to say that possible sensible moves are about 10^40 while and 10^120 while taking any moves (maybe including some illogical / illegal ones) .

Shannon's estimate was based on very primitive methods; by generating random positions and using fairly advanced methods to see whether they are legal or not (ie., can you construct a proof game for it, or prove that it could never happen), you will get much closer. A group of people have been working on this, and their current best estimate is (4.822 +- 0.028) * 10^44, or a bit over 148 bits. (Amazingly enough, Shannon wasn't all that far off on this account! His estimated number of legal games seems much more dodgy, though.)

http://talkchess.com/forum3/viewtopic.php?f=7&t=77685&sid=e3...

Practically speaking, https://github.com/tromp/ChessPositionRanking gives a number between 0 and approx. 8.7 * 10^45 for any legal position, so it's only a couple of bits away from optimality.

The number of chess positions has now been estimated with 2 digits of accuracy as ~ 4.8 x 10^44: https://github.com/tromp/ChessPositionRanking