1 ! Copyright (C) 2008 Daniel Ehrenberg.
\r
2 ! See http://factorcode.org/license.txt for BSD license.
\r
3 USING: kernel sequences arrays accessors grouping math.order
\r
4 sorting binary-search math assocs locals namespaces make ;
\r
7 TUPLE: interval-map array ;
\r
15 : find-interval ( key interval-map -- interval-node )
\r
16 array>> [ start <=> ] with search nip ;
\r
18 : interval-contains? ( key interval-node -- ? )
\r
19 [ start ] [ end ] bi between? ;
\r
21 : all-intervals ( sequence -- intervals )
\r
22 [ [ dup number? [ dup 2array ] when ] dip ] { } assoc-map-as ;
\r
24 : disjoint? ( node1 node2 -- ? )
\r
25 [ end ] [ start ] bi* < ;
\r
27 : ensure-disjoint ( intervals -- intervals )
\r
28 dup [ disjoint? ] monotonic?
\r
29 [ "Intervals are not disjoint" throw ] unless ;
\r
31 : >intervals ( specification -- intervals )
\r
32 [ suffix ] { } assoc>map concat 3 <groups> ;
\r
36 : interval-at* ( key map -- value ? )
\r
37 [ drop ] [ find-interval ] 2bi
\r
38 [ nip ] [ interval-contains? ] 2bi
\r
39 [ value t ] [ drop f f ] if ;
\r
41 : interval-at ( key map -- value ) interval-at* drop ;
\r
43 : interval-key? ( key map -- ? ) interval-at* nip ;
\r
45 : interval-values ( map -- values )
\r
46 array>> [ value ] map ;
\r
48 : <interval-map> ( specification -- map )
\r
49 all-intervals [ first second ] sort-with
\r
50 >intervals ensure-disjoint interval-map boa ;
\r
52 : <interval-set> ( specification -- map )
\r
53 dup zip <interval-map> ;
\r
55 :: coalesce ( alist -- specification )
\r
56 ! Only works with integer keys, because they're discrete
\r
59 alist sort-keys unclip swap [ [ first dup ] [ second ] bi ] dip
\r
60 [| oldkey oldval key val | ! Underneath is start
\r
63 [ oldkey 2array oldval 2array , key ] unless
\r
65 ] assoc-each [ 2array ] bi@ ,
\r