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  • Attributes memory overhead

    Posted by unterrainer_ale on September 1, 2023 at 12:00 am

    Out of curiosity, can anyone explain the attributes overhead as explained in the Abridged Q Language Manual? Does anyone know what the 4*u+1 is? for parted and grouped? (I know the 4byte should be probably 8 bytes after 3.0)

    example overhead
    `s#2 2 3 sorted 0
    `u#2 4 5 unique 16*u
    `p#2 2 1 parted (4*u;16*u;4*u+1)
    `g#2 1 2 grouped (4*u;16*u;4*u+1;4*n)

    The byte overheads use n(number of elements) and u(number of uniques). These are used by lookups, e.g.

    unterrainer_ale replied 3 months, 1 week ago 2 Members · 1 Reply
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