26 lines
1.2 KiB
Text
26 lines
1.2 KiB
Text
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Ideal Hash Array Mapped Tries: an Erlang functional datatype
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The Hash Array Mapped Trie (HAMT) is based on the simple notion of hashing a
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key and storing the key in a trie based on this hash value. The AMT is used to
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implement the required structure e#ciently. The Array Mapped Trie (AMT) is a
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versatile data structure and yields attractive alternative to contemporary
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algorithms in many applications. Here I describe how it is used to develop Hash
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Trees with near ideal characteristics that avoid the traditional problem,
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setting the size of the initial root hash table or incurring the high cost of
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dynamic resizing to achieve an acceptable performance.
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Based on the paper "Ideal Hash Tries" by Phil Bagwell [2000].
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@ARTICLE{Bagwell01idealhash,
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author = {Phil Bagwell},
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title = {Ideal Hash Trees},
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journal = {Es Grands Champs},
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year = {2001},
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volume = {1195}
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}
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http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.21.6279
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http://lampwww.epfl.ch/papers/idealhashtrees.pdf
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http://en.wikipedia.org/wiki/Hash_array_mapped_trie
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This is an experiment in functional datatypes in Erlang. At some point I'll
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mature this into a persistent concurrent hash array mapped trie (ctrie).
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