I have just released an updated version of my Colossus engine on my website at http://www.colossusgames.somee.com
I have perfomed a major tidy up from the previous version with various bug fixes and tuning.
My tests indicate an improvement of about 25 ELO.
I have also installed Colossus as a bot on the lichess website so if you fancy challenging it online search for ColossusBOT
Merry Christmas everyone!
Colossus 2024a now available
Moderator: Ras
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- Full name: Martin Bryant
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Re: Colossus 2024a now available
This is exciting news Martin. Many thanks.
Thanks for this Christmas version !!
Thanks for this Christmas version !!
What seems like a fairy tale today may be reality tomorrow.
Here we have a fairy tale of the day after tomorrow....
Here we have a fairy tale of the day after tomorrow....
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Re: Colossus 2024a now available
Thanks Martin
Regards from Cheshire
Bryan Whitby
Regards from Cheshire
Bryan Whitby
What's my next move? - to the fridge for another beer !!
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Re: Colossus 2024a now available
Thanks Martin.MartinBryant wrote: ↑Mon Dec 09, 2024 2:00 pm I have just released an updated version of my Colossus engine on my website at http://www.colossusgames.somee.com
I have perfomed a major tidy up from the previous version with various bug fixes and tuning.
My tests indicate an improvement of about 25 ELO.
I have also installed Colossus as a bot on the lichess website so if you fancy challenging it online search for ColossusBOT
Merry Christmas everyone!
Please explain what the MateAllChecks and other such parameters do.
Marek Soszynski
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Re: Colossus 2024a now available
Ah... I've added a mate finder mode to Colossus (via the UCI 'go mate n' command) but it's still a work in progress so I didn't mention it yet.Marek Soszynski wrote: ↑Mon Dec 09, 2024 7:18 pmThanks Martin.MartinBryant wrote: ↑Mon Dec 09, 2024 2:00 pm I have just released an updated version of my Colossus engine on my website at http://www.colossusgames.somee.com
I have perfomed a major tidy up from the previous version with various bug fixes and tuning.
My tests indicate an improvement of about 25 ELO.
I have also installed Colossus as a bot on the lichess website so if you fancy challenging it online search for ColossusBOT
Merry Christmas everyone!
Please explain what the MateAllChecks and other such parameters do.
But you can try it of course

It works well in some cases and not so well in others!
The extra UCI switches allow you to specify whether the search should only include checks, mate-in-1 threats, zero-king-moves or fixed pieces similar to the parameters you can specify with the Chest mate finder program.
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Re: Colossus 2024a now available
Hi!
Thanks for the new version, regards
MartinBryant wrote: ↑Mon Dec 09, 2024 10:39 pm The extra UCI switches allow you to specify whether the search should only include checks, mate-in-1 threats, zero-king-moves or fixed pieces similar to the parameters you can specify with the Chest mate finder program.
Which kind of string is to be typed as for this one UCI- option, please? Chest's one I know similiar to that only PieceLimit.option name MateFixedPieces type string
Thanks for the new version, regards
Peter.
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Re: Colossus 2024a now available
I configured Colossus in Arena.
I set the path for the EGT and attempted to use the analyze feature of Arena.
I am not seeing any output.
If I run the engine from a folder, I first type "UCI", then "go infinite". I see output.
Arena is doing the same thing...here is some dialog between the engine and Arena.
I set the path for the EGT and attempted to use the analyze feature of Arena.
I am not seeing any output.
If I run the engine from a folder, I first type "UCI", then "go infinite". I see output.
Arena is doing the same thing...here is some dialog between the engine and Arena.
Code: Select all
2024-12-09 23:42:55.125 Arena 3.5.1
2024-12-09 23:42:55.141
2024-12-09 23:42:55.638**----------New game---2024-12-09 23:42:55,638 Mon -------------
2024-12-09 23:42:55.721**screen: 2560x1440
2024-12-09 23:42:55.721**Monitors: 1
2024-12-09 23:42:55.721**Monitor0: 2560x1440
2024-12-09 23:42:55.721**FormMonitor: 0
2024-12-09 23:42:55.721**DesktopRect: 0/0 .. 2560/1440
2024-12-09 23:42:55.789**Loading 1
2024-12-09 23:43:02.015*1*----------------------Starting engine 1 Colossus2024a-----------------------
2024-12-09 23:43:02.016*1*Configured Engine 1 Type: Auto
2024-12-09 23:43:02.016*1*Engine 1 dir: E:\Chess\Arena\Engines\Colossus
2024-12-09 23:43:02.016*1*Engine 1 commandline: E:\Chess\Arena\Engines\Colossus\Colossus2024a.exe
2024-12-09 23:43:02.138*1*Child Process Prio Adj: PID 28516 conhost.exe
2024-12-09 23:43:02.138*1*Engine 1 ProcessID: 26652
2024-12-09 23:43:02.138*1*Engine 1 Prio:32 ThreadPrio:0
2024-12-09 23:43:02.138-->1:xboard
2024-12-09 23:43:02.165<--1:info string *** Unknown command!: xboard
2024-12-09 23:43:02.165-->1:uci
2024-12-09 23:43:02.165<--1:id name Colossus 2024a
2024-12-09 23:43:02.165<--1:id author Martin Bryant
2024-12-09 23:43:02.165<--1:option name Hash type spin default 64 min 0 max 16384
2024-12-09 23:43:02.165<--1:option name Threads type spin default 1 min 1 max 64
2024-12-09 23:43:02.165<--1:option name ClearHash type button
2024-12-09 23:43:02.165<--1:option name Ponder type check default false
2024-12-09 23:43:02.165<--1:option name SyzygyPath type string
2024-12-09 23:43:02.165<--1:option name UCI_Chess960 type check default false
2024-12-09 23:43:02.165<--1:option name MateAllChecks type check default false
2024-12-09 23:43:02.165<--1:option name MateAllThreateningMateInOne type check default false
2024-12-09 23:43:02.166<--1:option name MateAllZeroKingMoves type check default false
2024-12-09 23:43:02.166<--1:option name MateFixedPieces type string
2024-12-09 23:43:02.166<--1:uciok
2024-12-09 23:43:02.166-->1:setoption name Hash value 16384
2024-12-09 23:43:02.166-->1:setoption name Threads value 6
2024-12-09 23:43:02.166-->1:setoption name SyzygyPath value H:\syzygy
2024-12-09 23:43:02.170*1*Child Process Prio Adj: PID 28516 conhost.exe
2024-12-09 23:43:02.170<--1:info string Transposition table memory set to 16384MB
2024-12-09 23:43:02.171<--1:info string Threads set to 6
2024-12-09 23:43:02.172-->1:isready
2024-12-09 23:43:02.228<--1:info string 6-piece endgame tablebases found at H:\syzygy
2024-12-09 23:43:02.228<--1:readyok
2024-12-09 23:43:02.388**Time for starting engines for analysis:375 ms
2024-12-09 23:43:02.388-->1:isready
2024-12-09 23:43:02.388<--1:readyok
2024-12-09 23:43:02.390-->1:ucinewgame
2024-12-09 23:43:02.390-->1:isready
2024-12-09 23:43:02.390<--1:readyok
2024-12-09 23:43:02.406-->1:position fen 5B2/4n3/p1k1p1p1/P1P1n2p/4P2P/1p3B2/3K4/6R1 w - - 0 1
2024-12-09 23:43:02.406-->1:go infinite
2024-12-09 23:43:02.406**Time for starting analysis:406
2024-12-09 23:43:08.664-->1:stop
i7-6700K @ 4.00Ghz 32Gb, Win 10 Home, EGTBs on PCI SSD
Benchmark: Stockfish15.1 NNUE x64 bmi2 (nps): 1277K
Benchmark: Stockfish15.1 NNUE x64 bmi2 (nps): 1277K
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Re: Colossus 2024a now available
That was exactly the case for me, but it still works if you change the name of the folder to arena.MOBMAT wrote: ↑Tue Dec 10, 2024 7:44 am I configured Colossus in Arena.
I set the path for the EGT and attempted to use the analyze feature of Arena.
I am not seeing any output.
If I run the engine from a folder, I first type "UCI", then "go infinite". I see output.
Arena is doing the same thing...here is some dialog between the engine and Arena.
Code: Select all
2024-12-09 23:42:55.125 Arena 3.5.1 2024-12-09 23:42:55.141 2024-12-09 23:42:55.638**----------New game---2024-12-09 23:42:55,638 Mon ------------- 2024-12-09 23:42:55.721**screen: 2560x1440 2024-12-09 23:42:55.721**Monitors: 1 2024-12-09 23:42:55.721**Monitor0: 2560x1440 2024-12-09 23:42:55.721**FormMonitor: 0 2024-12-09 23:42:55.721**DesktopRect: 0/0 .. 2560/1440 2024-12-09 23:42:55.789**Loading 1 2024-12-09 23:43:02.015*1*----------------------Starting engine 1 Colossus2024a----------------------- 2024-12-09 23:43:02.016*1*Configured Engine 1 Type: Auto 2024-12-09 23:43:02.016*1*Engine 1 dir: E:\Chess\Arena\Engines\Colossus 2024-12-09 23:43:02.016*1*Engine 1 commandline: E:\Chess\Arena\Engines\Colossus\Colossus2024a.exe 2024-12-09 23:43:02.138*1*Child Process Prio Adj: PID 28516 conhost.exe 2024-12-09 23:43:02.138*1*Engine 1 ProcessID: 26652 2024-12-09 23:43:02.138*1*Engine 1 Prio:32 ThreadPrio:0 2024-12-09 23:43:02.138-->1:xboard 2024-12-09 23:43:02.165<--1:info string *** Unknown command!: xboard 2024-12-09 23:43:02.165-->1:uci 2024-12-09 23:43:02.165<--1:id name Colossus 2024a 2024-12-09 23:43:02.165<--1:id author Martin Bryant 2024-12-09 23:43:02.165<--1:option name Hash type spin default 64 min 0 max 16384 2024-12-09 23:43:02.165<--1:option name Threads type spin default 1 min 1 max 64 2024-12-09 23:43:02.165<--1:option name ClearHash type button 2024-12-09 23:43:02.165<--1:option name Ponder type check default false 2024-12-09 23:43:02.165<--1:option name SyzygyPath type string 2024-12-09 23:43:02.165<--1:option name UCI_Chess960 type check default false 2024-12-09 23:43:02.165<--1:option name MateAllChecks type check default false 2024-12-09 23:43:02.165<--1:option name MateAllThreateningMateInOne type check default false 2024-12-09 23:43:02.166<--1:option name MateAllZeroKingMoves type check default false 2024-12-09 23:43:02.166<--1:option name MateFixedPieces type string 2024-12-09 23:43:02.166<--1:uciok 2024-12-09 23:43:02.166-->1:setoption name Hash value 16384 2024-12-09 23:43:02.166-->1:setoption name Threads value 6 2024-12-09 23:43:02.166-->1:setoption name SyzygyPath value H:\syzygy 2024-12-09 23:43:02.170*1*Child Process Prio Adj: PID 28516 conhost.exe 2024-12-09 23:43:02.170<--1:info string Transposition table memory set to 16384MB 2024-12-09 23:43:02.171<--1:info string Threads set to 6 2024-12-09 23:43:02.172-->1:isready 2024-12-09 23:43:02.228<--1:info string 6-piece endgame tablebases found at H:\syzygy 2024-12-09 23:43:02.228<--1:readyok 2024-12-09 23:43:02.388**Time for starting engines for analysis:375 ms 2024-12-09 23:43:02.388-->1:isready 2024-12-09 23:43:02.388<--1:readyok 2024-12-09 23:43:02.390-->1:ucinewgame 2024-12-09 23:43:02.390-->1:isready 2024-12-09 23:43:02.390<--1:readyok 2024-12-09 23:43:02.406-->1:position fen 5B2/4n3/p1k1p1p1/P1P1n2p/4P2P/1p3B2/3K4/6R1 w - - 0 1 2024-12-09 23:43:02.406-->1:go infinite 2024-12-09 23:43:02.406**Time for starting analysis:406 2024-12-09 23:43:08.664-->1:stop
Windows 10:
original name in windows: C:\Program Files\arena_3.5.1\TB\syzygy
in Arena: C:\Programme\arena_3.5.1\TB\syzygy
Then it works.
FEN: 7k/5pp1/8/8/8/8/1K6/R7 w - - 0 1
Colossus 2024a:
Colossus 2024a von Martin Bryant
6-piece endgame tablebases found at C:\Programme\arena_3.5.1\TB\syzygy
Code: Select all
251453 >first : quit
251859*1*------------------------Starte Motor 1 Colossus2024a------------------------
251859*1*Configured Engine 1 Type: Auto
251859*1*Engine 1 dir: C:\Program Files\arena_3.5.1\Engines\Colossus2024a
251859*1*Engine 1 commandline: "C:\Program Files\arena_3.5.1\Engines\Colossus2024a\Colossus2024a.exe"
251984*1*Child Process Prio Adj: PID 4384 conhost.exe
251984*1*Engine 1 ProcessID: 3260
251984*1*Engine 1 Prio:32 ThreadPrio:0
251984 >first : xboard
252031 >first : uci
252031 <first : id name Colossus 2024a
252031 <first : id author Martin Bryant
252031 <first : option name Hash type spin default 64 min 0 max 16384
252031 <first : option name Threads type spin default 1 min 1 max 64
252031 <first : option name ClearHash type button
252031 <first : option name Ponder type check default false
252031 <first : option name SyzygyPath type string
252047 <first : option name UCI_Chess960 type check default false
252047 <first : option name MateAllChecks type check default false
252047 <first : option name MateAllThreateningMateInOne type check default false
252047 <first : option name MateAllZeroKingMoves type check default false
252047 <first : option name MateFixedPieces type string
252047 <first : uciok
252047 >first : setoption name SyzygyPath value C:\Programme\arena_3.5.1\TB\syzygy
252047*1*Child Process Prio Adj: PID 4384 conhost.exe
252062 >first : isready
252219 <first : readyok
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- Full name: Peter Martan
Re: Colossus 2024a now available
Indeed there seems to be a problem with Syzygy tbs in Arena as well as in Shredder. Engine runs without problems as long as no path to tbs is set, UCI- option in GUI edited, engine doesn't start running anymore.
If you empty the UCI- field in GUI doesn't help neither without new start of GUI, but a text- file called Colossus2024a.exe.16380.error.txt is written in directory of binary:
Tried to edit Colossus.ini as for inititalisation command as described in .ini too, didn't help neither, regards
If you empty the UCI- field in GUI doesn't help neither without new start of GUI, but a text- file called Colossus2024a.exe.16380.error.txt is written in directory of binary:
Starting the default setting with its original name in GUI without tbs- path works normally again.*** Error!: No endgame tablebases found at <empty>
Tried to edit Colossus.ini as for inititalisation command as described in .ini too, didn't help neither, regards
Peter.
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- Location: Manchester, UK
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Re: Colossus 2024a now available
The MateFixedPieces option would be used for those mating positions where e.g. you get a bunch of the defender's pieces blocked in a corner. So you can tell the engine that certain pieces are 'fixed' on certain squares and if it ever searches a line where those pieces can move then it prunes that line thus speeding up the solution.peter wrote: ↑Tue Dec 10, 2024 1:03 am Hi!MartinBryant wrote: ↑Mon Dec 09, 2024 10:39 pm The extra UCI switches allow you to specify whether the search should only include checks, mate-in-1 threats, zero-king-moves or fixed pieces similar to the parameters you can specify with the Chest mate finder program.Which kind of string is to be typed as for this one UCI- option, please? Chest's one I know similiar to that only PieceLimit.option name MateFixedPieces type string
Thanks for the new version, regards
The syntax is just a string of the squares in algebraic notation e.g.
setoption name matefixedpieces value a1b1a2b2
This tells it to prune any lines if the pieces on a1, b2, a2 or b2 are ever allowed to move.
It works well in some positions but annoyingly you sometimes find that a piece that looks 'fixed' can validly move in some obscure sub-variation

But like I said... a work in progress.