46 lines
1.8 KiB
Factor
Executable File
46 lines
1.8 KiB
Factor
Executable File
! Copyright (C) 2008 Marc Fauconneau.
|
|
! See http://factorcode.org/license.txt for BSD license.
|
|
USING: arrays help.markup help.syntax io.streams.string
|
|
sequences strings math suffix-arrays.private ;
|
|
IN: suffix-arrays
|
|
|
|
HELP: >suffix-array
|
|
{ $values
|
|
{ "seq" sequence }
|
|
{ "array" array } }
|
|
{ $description "Creates a suffix array from the input sequence. Suffix arrays are arrays of slices." } ;
|
|
|
|
HELP: SA{
|
|
{ $description "Creates a new literal suffix array at parse-time." } ;
|
|
|
|
HELP: suffixes
|
|
{ $values
|
|
{ "string" string }
|
|
{ "suffixes-seq" "a sequence of slices" } }
|
|
{ $description "Returns a sequence of tail slices of the input string." } ;
|
|
|
|
HELP: from-to
|
|
{ $values
|
|
{ "index" integer } { "begin" sequence } { "suffix-array" "a suffix-array" }
|
|
{ "from/f" "an integer or f" } { "to/f" "an integer or f" } }
|
|
{ $description "Finds the bounds of the suffix array that match the input sequence. A return value of " { $link f } " means that the endpoint is included." }
|
|
{ $notes "Slices are [m,n) and we want (m,n) so we increment." } ;
|
|
|
|
HELP: query
|
|
{ $values
|
|
{ "begin" sequence } { "suffix-array" "a suffix-array" }
|
|
{ "matches" array } }
|
|
{ $description "Returns a sequence of sequences from the suffix-array that contain the input sequence. An empty array is returned when there are no matches." } ;
|
|
|
|
ARTICLE: "suffix-arrays" "Suffix arrays"
|
|
"The " { $vocab-link "suffix-arrays" } " vocabulary implements the suffix array data structure for efficient lookup of subsequences. This suffix array implementation is a sorted array of suffixes. Querying it for matches uses binary search for efficiency." $nl
|
|
|
|
"Creating new suffix arrays:"
|
|
{ $subsection >suffix-array }
|
|
"Literal suffix arrays:"
|
|
{ $subsection POSTPONE: SA{ }
|
|
"Querying suffix arrays:"
|
|
{ $subsection query } ;
|
|
|
|
ABOUT: "suffix-arrays"
|