1 ! Copyright (C) 2009 Daniel Ehrenberg.
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: accessors alien.c-types arrays assocs binary-search
4 combinators fry grouping kernel locals make math math.order
5 sequences sequences.private sorting specialized-arrays ;
6 SPECIALIZED-ARRAY: uint
8 ! Sets of positive integers
10 TUPLE: interval-set { array uint-array read-only } ;
14 ALIAS: start first-unsafe
15 ALIAS: end second-unsafe
17 : find-interval ( key interval-set -- slice )
18 array>> 2 <sliced-groups>
19 [ start <=> ] with search nip ; inline
21 ERROR: not-an-interval-set obj ;
23 : check-interval-set ( map -- map )
24 dup interval-set? [ not-an-interval-set ] unless ; inline
28 : in? ( key set -- ? )
29 check-interval-set dupd find-interval
30 [ [ start ] [ end 1 - ] bi between? ]
35 : spec>pairs ( sequence -- intervals )
36 [ dup number? [ dup 2array ] when ] map ;
38 : disjoint? ( node1 node2 -- ? )
39 [ end ] [ start ] bi* < ;
41 : (delete-redundancies) ( seq -- )
53 : delete-redundancies ( seq -- seq' )
54 ! If the next element is >= current one, leave out both
55 [ (delete-redundancies) ] uint-array{ } make ;
57 : make-intervals ( seq -- interval-set )
62 : >intervals ( seq -- seq' )
63 [ 1 + ] assoc-map concat ;
67 : <interval-set> ( specification -- interval-set )
69 >intervals make-intervals ;
73 :: or-step ( set1 set2 -- set1' set2' )
75 set1 second set2 first <=
76 [ set1 0 ] [ set2 2 ] if
77 [ second , ] [ set2 swap tail-slice ] bi*
80 : combine-or ( set1 set2 -- )
82 { [ over empty? ] [ % drop ] }
83 { [ dup empty? ] [ drop % ] }
93 : <interval-or> ( set1 set2 -- set )
95 [ combine-or ] uint-array{ } make
100 : prefix-0 ( seq -- 0seq )
101 0 over ?nth zero? [ rest ] [ 0 prefix ] if ;
103 : interval-max ( interval-set1 interval-set2 -- n )
104 [ array>> [ 0 ] [ last ] if-empty ] bi@ max ;
108 : <interval-not> ( set maximum -- set' )
109 [ array>> prefix-0 ] dip suffix make-intervals ;
111 : <interval-and> ( set1 set2 -- set )
113 [ '[ _ <interval-not> ] bi@ <interval-or> ] keep