chess:programming:transposition_table
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| A transposition table makes uses of Hash functions to convert chess positions into an almost unique, scalar signature, allowing fast index calculation as well as space saving verification of stored positions. | A transposition table makes uses of Hash functions to convert chess positions into an almost unique, scalar signature, allowing fast index calculation as well as space saving verification of stored positions. | ||
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| + | ===== Disadvantage of Transposition Tables ===== | ||
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| + | The major disadvantage of transposition tables is their size. | ||
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| + | **Refutation tables** attempt to retain one of the advantages of transposition tables, when used with iterative deepening, but with smaller memory requirements. | ||
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| + | * For each iteration, the search yields a path for each move from the root to a leaf node that results in either the correct minimax score or an upper bound on its value. | ||
| + | * This path from the d-1 ply search can be used as the basis for the search to d ply. | ||
| + | * Often, searching the previous iteration’s path or refutation for a move as the initial path examined for the current iteration will prove sufficient to refute the move one ply deeper. | ||
chess/programming/transposition_table.1634035184.txt.gz · Last modified: 2021/10/12 10:39 by peter