Questions tagged [transpositions]
A transposition is when a series of moves leads a game from one opening into another.
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How to calculate transposition table hash index
I'm writing a chess engine in Java, and I'm having difficulty understanding how to calculate the hash address/index, based on the zobrist key.
According to the Chess Programming Wiki, since the 64-bit ...
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Help with Negamax using transposition table
I've recently been improving my Negamax algorithm for chess, adding a transposition table. The algorithm was working well before this addition. After this addition I can't see no big improvements in ...
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London system move order nuances Qb6 without Nc6
In the London system, playing early Nd2 is recommended to react against Qb6. For example if we take this move order
[FEN ""]
1. d4 d5 2. Bf4 Nf6 3. e3 c5 4. c3 Nc6 5. Nd2 Qb6 6....
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Iterative deepening speed expectation
I have developed a chess engine with these features:
alpha beta
transposition tables
iterative deepening
use any prev result from transposition table as first move if the result cannot be used ...
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What do QGA players usually play when White doesn't play exactly 1.d4 d5 2.c4?
If Black plays the KID, then Black can play Nf6, g6, Bg7, O-O, d6 against everything.
If Black plays the QGD, then Black can play d5, e6, Nf6, Be7, O-O against everything.
If Black plays the Slav ......
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Transposition table produces diffrent and wrong search results
I am currently developing my own chess engine in rust. It all was working pretty fine, until I added transposition tables. Where my engine was playing the reasonable move e2e4 at a lower depth, with ...
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How to avoid the Sicilian after 1.e4 d6 2.Nf3?
I am learning the Pirc Defense as black. I am a bit confused when after 1.e4 d6 white plays 2.Nf3. Are they forcing me to transpose into a Sicilian with 2... c5? I kind of like the Sicilian Dragon, so ...
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My Transposition Tables implementation slows down Alpha Beta Pruning
I have this implementation of alpha beta pruning I made a couple days ago. I've been trying to look into transposition tables.
When I tried this implementation it was slower than the original code. I ...
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How to understand which positions result from certain opening
I was watching Irina Krush's great lecture on YouTube and, at 20:06, she asks "Which opening is this position from?" The answer is apparently the Sicilian, which made me wonder. How do you ...
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Marshall Defense transposition to Gruenfeld
Can this move order be considered a good surprise weapon against 1.d4 players since the Marshall Defense is known to be dubious and now black is trying to transpose it to a Gruenfeld. From my ...
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Transposition Tables Bug, implementation produces different results
I've been writing my chess engine for 2 months now, and I've come across this bug that I can't manage to solve. Basically, when I disable my transposition table, the engine plays fine and the minimax ...
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Transposition into KID
I have looked at many grandmaster games where White starts off with 1.c4, which later mostly transposes into a King's Indian. However, Black could have immediately played 1...e5, which seems slightly ...
user24344
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Hanham Variation Philidor Defense
I want to find a way of transposing into the Hanham Variation of the Philidor Defense, without a way for White to deviate. For example, in the normal move order, White may have the move 3. Bc4 or 3. ...
user24344
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Transposition Tables
Are transposition tables (in engines) used for one or multiple games?
My current knowledge of transposition tables is that when an engine searches the game tree, there will sometimes be positions ...
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Is there a root tree of openings based on response by Black and vice versa?
I'm enjoying my study as a relative noob into chess (1000 rapid in Lichess and on Chess.com in the last month or so) and am getting very interested in openings.
Is there a relative root tree that you ...
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Stockfish Transposition Table: 16 bit key equals 0 even if the key is found? [closed]
In Stockfish 11, they use the high 16 bits as key inside the cluster:
const uint16_t key16 = key >> 48; // Use the high 16 bits as key inside the cluster
This renders problem when key >> ...
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How this game is denoted as French Advanced Variation?
I had started playing this game with Scandinavian Defense opening. How it is been denoted as French Advanced variation as of 3rd move. Please refer to the attached screen-shot.
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1. e4 e6 2. d4 c5 - is this opening worth it?
While doing my spring cleaning, I came across an old book claiming to give a good opening chance for black. It's called the "Barcza-Larsen opening" and it is characterized by 2 .. c5:
[fen ""]
1. e4 ...
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Most different openings by transpositions?
What sequence of opening moves can include most different named Openings or Defenses by transpositions?
For example, I just played a bullet game that went:
1.d4 e5 2. e4 d6 3. Nf3 Nc6 4. Bb5.
In ...
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Are there any sources of massive transposition tables?
Do transposition databases exist the way tablebases do? Would an engine be able to take advantage of a pre-calculated TD? Is there a benefit to players when studying if they had access to pre-...
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Why is 5...Be7 played before ...b5 in the main line of the Closed Ruy Lopez?
Here is what I've seen described as the main line of the Closed Ruy Lopez up to move 7:
[fen ""]
1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6
5. O-O Be7 (5... b5 6. Bb3 Be7 7. Re1 d6) 6. Re1 b5 7. Bb3 ...
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Opening classification and transpositions
Positions in an opening can often be reached in a variety of (meaningful) ways, i.e. by transpositions.
When classifying chess games (e.g. in databases or books) by , are there rules or other ...
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Marshall Defense 1.d4 d5 2.c4 Nf6 — transpositions
I know that the theoretical refutation of 1.d4 d5 2.c4 Nf6?! is supposed to be 3.cxd5 Nxd5 4.Nf3.
Perhaps Black doesn't fear the refutation because he intends a gambit such as 3.cxd5 c6?! or 3.cxd5 ...
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Three-fold repetition and null move
Added transposition table (this was tested alone and worked as expected), three fold repetition and null move pruning in my engine and wins more games but some of them end with three fold repetition ...
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multi PVs using triangular array
I am currently using a triangular array to collect the PV in my chess engine (written in C). However, I would like to return several variations such as the second best, third best, and so fourth. Is ...
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What are all the most common transpositions between the Caro-Kann Panov–Botvinnik Attack with 5...e6 6. Nf3 Bb4 and the Nimzo-Indian Defence?
I would like to know what are all the most frequent transpositions between the two following openings:
.
The Caro-Kann Panov–Botvinnik Attack with 5...e6 6. Nf3 Bb4:
[StartPly "12"]
[FEN ""]
...
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Why is it said that beginning with 1. Nf3 2. c4 avoids the Benoni but beginning with 1. d4 2. c4 does not?
I have read a lot of messages on different Forums about the merits of beginning with 1.Nf3 or beginning with 1.d4.
And a very big number of people said essentially this:
One of the advantages of ...
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Can the Nc3+e3 Chebanenko Slav, the Exchange Slav and the 4...Bg4 Slow Slav transpose into each other?
I would like to know if the following three variations can transpose into each other?
The Nc3+e3 Chebanenko Slav: 1. d4 d5 2. c4 c6 3. Nc3 Nf6 4. e3 a6
The Exchange Slav: 1. d4 d5 2. c4 c6 3. cxd5 ...
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Is there any transposition available in between QGA and other openings?
I'm a chess player with ELO 1600. Now I'm trying to learn transpositions in chess. QGA is my favorite opening as white. But most of the time black chooses Queen's Gambit Declined. So now I'm trying to ...
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Kind of popular variation in Tournament
I am just an ordinary chess player who does not know about Chess Tournament even just a little thing,
as I saw at my Houdini vs my Houdini at Tournament level in 5 minutes (and now I still testing in ...
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How can one determine the opening or transposed opening from the existing pawn formation/structure?
I was once told that you can determine an opening or transposed opening just by how the pawns are structured on the board. Is this the method normally used to determine if an opening was transposed ...
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Can a set of moves be a transposition and a variation?
I am confused about the differences between a transposition and variation. I know that a transposition is when you start of with one opening and a set of moves after that leads to another opening and ...
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