freebsd-ports/textproc/p5-Algorithm-RabinKarp/pkg-descr
Stefan Eßer fb16dfecae Remove WWW entries moved into port Makefiles
Commit b7f05445c0 has added WWW entries to port Makefiles based on
WWW: lines in pkg-descr files.

This commit removes the WWW: lines of moved-over URLs from these
pkg-descr files.

Approved by:		portmgr (tcberner)
2022-09-07 23:58:51 +02:00

16 lines
788 B
Plaintext

This is an implementation of Rabin and Karp's streaming hash, as described
in "Winnowing: Local Algorithms for Document Fingerprinting" by Schleimer,
Wilkerson, and Aiken. Following the suggestion of Schleimer, I am using
their second equation:
$H[ $c[2..$k + 1] ] = (( $H[ $c[1..$k] ] - $c[1] ** $k ) + $c[$k+1] ) * $k
The results of this hash encodes information about the next k values in
the stream (hense k-gram.) This means for any given stream of length n
integer values (or characters), you will get back n - k + 1 hash values.
For best results, you will want to create a code generator that filters
your data to remove all unnecessary information. For example, in a large
english document, you should probably remove all white space, as well as
removing all capitalization.