Showing papers on "Feature hashing published in 1991"
08 Apr 1991
TL;DR: A trial-and-error method of finding perfect hashing functions is proposed using a simple universal/sub 2/ class (H/sub 3/) of hashing functions, and the results show that the relative frequency ofperfect hashing functions within the class H/ sub 3/ is the same as predicted by the analysis for the set of all functions.
Abstract: Perfect hashing functions are determined that are suitable for hardware implementations. A trial-and-error method of finding perfect hashing functions is proposed using a simple universal/sub 2/ class (H/sub 3/) of hashing functions. The results show that the relative frequency of perfect hashing functions within the class H/sub 3/ is the same as predicted by the analysis for the set of all functions. Extensions of the basic scheme can handle dynamic key sets and large key sets. Perfect hashing functions can be found using software, and then loaded into the hardware hash address generator. Inexpensive associative memory can be used as a general memory construct offered by the system services of high-performance (super) computers. It has a potential application for storing operating system tables or internal tables for software development tools, such as compilers, assemblers and linkers. Perfect hashing in hardware may find a number of other applications, such as high speed event counting and text searching. >
19 citations