hash table

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hash table

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hash table

A lookup table that is designed to efficiently store non-contiguous keys (account numbers, part numbers, etc.) that may have wide gaps in their alphabetic or numeric sequences.

Hash tables are created with an algorithm that stores the keys into hash buckets, which contain key-value pairs. Since different keys may hash to the same bucket, the goal of hash table design is to spread out the key-value pairs evenly with each bucket containing as few key-value pairs as possible. When an item is looked up, its key is hashed to find the appropriate bucket, and the bucket is then compared to find the right key-value pair. See key-value pair, cryptographic hash function, DHT and hash total.


A Hash Table
When an item is looked up, its key is hashed into a bucket value, and the bucket is compared to find the key.
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References in periodicals archive ?
On the other hand, although the proposed approach need to search vectors for the words within candidate extractions to compute the confidence score, the word vectors are stored in hashtable, which ensures the high efficiency over REVERB.
A hashtable is created which keeps track of a number of PropertyChangeListeners for Figs.
Some basic operations involved in this algorithm (and in Algorithm 2 and 3) include operation over stack, operation over hashtable and operation over vector.
Hashtable to store the relationship between customers and countries.
As shown, although the execution time of the first pass of EH-Apriori is slightly larger than that of E-Apriori, due to the extra overhead required for building HashTable, EH-Apriori incurs significantly smaller execution time than E-Apriori in the latter Pass 2, as |[C.sub.2]| is decreased greatly from 270355 to 115 by means of hash filtering (at T5-I3-W3-N1000-D100K, minimum support = 0.7%).
function hash (K: keytype; T: hashtable): integer; const prime = 1048583; var h, address: integer; begin h:=convertkey(K) mod prime; address:=h mod T.maxp; if address<T.p then address:=h mod(2*T.maxp); hash:=address; end;
Finally, the value which included the hashtable was inserted into the database system using the SQL query.
Similar to a traditional hashtable data structure, other operations supported in the DHT include put and get.
Perhaps the bottleneck may be a synchronized "Hashtable" that contains a list of currency exchange rate information for the current day.
The hash table itself, hashtable, is an array of pointers to word structures: #define HASHSIZE 07777 /* hash table size */ struct word [ char *word; /* the word */ int count; /* frequency count */ struct word *next; /* link to next entry */ ] *hashtable [HASHSIZE+1];