-USING: accessors arrays assocs combinators fry generalizations
-grouping growable kernel locals make math math.order math.ranges
-sequences sequences.deep sequences.private shuffle sorting
-splitting vectors ;
+USING: accessors arrays assocs combinators generalizations
+grouping growable heaps kernel math math.order ranges sequences
+sequences.private shuffle sorting splitting vectors ;
IN: sequences.extras
: find-all ( ... seq quot: ( ... elt -- ... ? ) -- ... elts )
[ length '[ 0 _ clamp ] bi@ ] keep subseq ;
: all-subseqs ( seq -- seqs )
- dup length [1,b] [ clump ] with map concat ;
+ dup length [1..b] [ clump ] with map concat ;
-:: each-subseq ( ... seq quot: ( ... subseq -- ... ) -- ... )
- seq length :> len
- len [0,b] [| from |
- from len (a,b] [| to |
- from to seq subseq quot call
- ] each
- ] each ; inline
+: each-subseq ( ... seq quot: ( ... subseq -- ... ) -- ... )
+ [ dup length [ [0..b] ] [ ] bi ] dip '[
+ dup _ (a..b] [ rot [ subseq _ call ] keep ] with each
+ ] each drop ; inline
: map-like ( seq exemplar -- seq' )
'[ _ like ] map ; inline
] keepdd map-like ; inline
: filter-all-subseqs ( ... seq quot: ( ... subseq -- ... ? ) -- seq )
- [ dup length [1,b] ] dip filter-all-subseqs-range ; inline
+ [ dup length [1..b] ] dip filter-all-subseqs-range ; inline
:: longest-subseq ( seq1 seq2 -- subseq )
seq1 length :> len1
0 :> n!
0 :> end!
len1 1 + [ len2 1 + 0 <array> ] replicate :> table
- len1 [1,b] [| x |
- len2 [1,b] [| y |
+ len1 [1..b] [| x |
+ len2 [1..b] [| y |
x 1 - seq1 nth-unsafe
y 1 - seq2 nth-unsafe = [
y 1 - x 1 - table nth-unsafe nth-unsafe 1 + :> len
: even-indices ( seq -- seq' )
[ length 1 + 2/ ] keep [
[ [ 2 * ] dip nth-unsafe ] curry
- ] keep map-integers ;
+ ] keep map-integers-as ;
: odd-indices ( seq -- seq' )
[ length 2/ ] keep [
[ [ 2 * 1 + ] dip nth-unsafe ] curry
- ] keep map-integers ;
+ ] keep map-integers-as ;
: compact ( ... seq quot: ( ... elt -- ... ? ) elt -- ... seq' )
[ split-when harvest ] dip join ; inline
: map-harvest ( ... seq quot: ( ... elt -- ... newelt ) -- ... newseq )
[ empty? not ] map-filter ; inline
+: (each-integer-with-previous) ( ... prev i n quot: ( ... i -- ... ) -- ... )
+ 2over < [
+ [ nip call ] 4keep nipdd
+ [ 1 + ] 2dip (each-integer-with-previous)
+ ] [
+ 4drop
+ ] if ; inline recursive
+
+: each-integer-with-previous ( ... n quot: ( ... i -- ... ) -- ... )
+ [ f 0 ] 2dip (each-integer-with-previous) ; inline
+
+: (collect-with-previous) ( quot into -- quot' )
+ [ [ keep ] dip [ set-nth-unsafe ] keepdd ] 2curry ; inline
+
+: collect-with-previous ( n quot into -- )
+ (collect-with-previous) each-integer-with-previous ; inline
+
+: map-integers-with ( ... len quot: ( ... prev i -- ... elt ) exemplar -- ... newseq )
+ overd [ [ collect-with-previous ] keep ] new-like ; inline
+
+: map-with-previous-as ( ... seq quot: ( ... elt prev/f -- ... newelt ) exemplar -- ... newseq )
+ [ length-operator ] dip map-integers-with ; inline
+
+: map-with-previous ( ... seq quot: ( ... elt prev/f -- ... newelt ) -- ... newseq )
+ over map-with-previous-as ; inline
+
<PRIVATE
: (setup-each-from) ( i seq -- n quot )
PRIVATE>
: map-from-as ( ... seq quot: ( ... elt -- ... newelt ) i exemplar -- ... newseq )
- [ -rot setup-each-from ] dip map-integers ; inline
+ [ -rot setup-each-from ] dip map-integers-as ; inline
: map-from ( ... seq quot: ( ... elt -- ... newelt ) i -- ... newseq )
pick map-from-as ; inline
+: map-if ( ... seq if-quot: ( ... elt -- ... ? ) map-quot: ( ... elt -- ... newelt ) -- ... newseq )
+ '[ dup @ _ when ] map ; inline
+
<PRIVATE
: push-map-if ( ..a elt filter-quot: ( ..a elt -- ..b ? ) map-quot: ( ..a elt -- ..b newelt ) accum -- ..b )
: 3each-from
( ... seq1 seq2 seq3 quot: ( ... elt1 elt2 elt3 -- ... ) i -- ... )
- [ (3each) ] dip -rot (each-integer) ; inline
+ [ (3each) ] dip -rot each-integer-from ; inline
: 3map-reduce
( ..a seq1 seq2 seq3 map-quot: ( ..a elt1 elt2 elt3 -- ..b intermediate ) reduce-quot: ( ..b prev intermediate -- ..a next ) -- ..a result )
: unsurround ( newseq seq2 seq3 -- seq1 )
[ ?head drop ] [ ?tail drop ] bi* ;
+: >string-list ( seq -- seq' )
+ [ "\"" 1surround ] map "," join ;
+
+: with-string-lines ( str quot -- str' )
+ [ string-lines ] dip map "\n" join ; inline
+
+: prepend-lines-with-spaces ( str -- str' )
+ [ " " prepend ] with-string-lines ;
+
: one? ( ... seq quot: ( ... elt -- ... ? ) -- ... ? )
[ find ] 2keep rot [
[ 1 + ] 2dip find-from drop not
] [ 3drop f ] if ; inline
: map-index! ( ... seq quot: ( ... elt index -- ... newelt ) -- ... seq )
- over [ [ (each-index) ] dip collect ] keep ; inline
+ over [ [ sequence-index-operator ] dip collect ] keep ; inline
<PRIVATE
pick [ 2map-into ] keep ; inline
: 2map-index ( ... seq1 seq2 quot: ( ... elt1 elt2 index -- ... newelt ) -- ... newseq )
- pick [ (2each-index) ] dip map-integers ; inline
+ pick [ (2each-index) ] dip map-integers-as ; inline
TUPLE: evens { seq read-only } ;
: until-empty ( seq quot -- )
[ dup empty? ] swap until drop ; inline
-: arg-max ( seq -- n )
- [ supremum ] keep index ;
-
-: arg-min ( seq -- n )
- [ infimum ] keep index ;
-
<PRIVATE
: push-index-if ( ..a elt i quot: ( ..a elt -- ..b ? ) accum -- ..b )
: zero-loop>array ( quot: ( ..a n -- ..a obj ) -- seq )
{ } zero-loop>sequence ; inline
+: iterate-heap-while ( heap quot1: ( value key -- slurp? ) quot2: ( value key -- obj/f ) -- obj/f loop? )
+ pick heap-empty?
+ [ 3drop f f ]
+ [
+ [ [ heap-peek ] 2dip drop 2keep ]
+ [
+ nip ! ( pop? value key heap quot2 )
+ 5roll [
+ swap heap-pop* call( value key -- obj/f ) t
+ ] [
+ 4drop f f
+ ] if
+ ] 3bi
+ ] if ; inline
+
+: slurp-heap-while-map ( heap quot1: ( value key -- slurp? ) quot2: ( value key -- obj/f ) -- seq )
+ '[ _ _ _ iterate-heap-while ] loop>array* ; inline
+
+: heap>pairs ( heap -- pairs )
+ [ 2drop t ] [ swap 2array ] slurp-heap-while-map ;
+
+: map-zip-swap ( quot: ( x -- y ) -- alist )
+ '[ _ keep ] map>alist ; inline
+
+: ?heap-pop-value>array ( heap -- array )
+ dup heap-empty? [ drop { } ] [ heap-pop drop 1array ] if ;
+
<PRIVATE
: (reverse) ( seq -- newseq )
[ 1 ] 2dip [ dip * ] curry [ swap ] prepose each ; inline
: insert-nth! ( elt n seq -- )
- [ length ] keep ensure swap pick (a,b]
+ [ length ] keep ensure swap pick (a..b]
over '[ [ 1 + ] keep _ move-unsafe ] each
set-nth-unsafe ;
[ length 1 - swap - ] [ nth ] bi ; inline
: each-index-from ( ... seq quot: ( ... elt index -- ... ) i -- ... )
- -rot (each-index) (each-integer) ; inline
+ -rot sequence-index-operator each-integer-from ; inline
<PRIVATE
: infimum-by* ( ... seq quot: ( ... elt -- ... x ) -- ... i elt )
[ before? ] select-by* ; inline
+: arg-max ( seq -- n )
+ [ ] supremum-by* drop ;
+
+: arg-min ( seq -- n )
+ [ ] infimum-by* drop ;
+
: ?supremum ( seq/f -- elt/f )
[ f ] [
[ ] [ 2dup and [ max ] [ dupd ? ] if ] map-reduce
] if-empty ;
: change-last ( seq quot -- )
- [ drop length 1 - ] [ change-nth ] 2bi ; inline
+ [ index-of-last ] [ change-nth ] bi* ; inline
: change-last-unsafe ( seq quot -- )
- [ drop length 1 - ] [ change-nth-unsafe ] 2bi ; inline
+ [ index-of-last ] [ change-nth-unsafe ] bi* ; inline
: replicate-into ( ... seq quot: ( ... -- ... newelt ) -- ... )
over [ length ] 2dip '[ _ dip _ set-nth-unsafe ] each-integer ; inline
: count* ( ... seq quot: ( ... elt -- ... ? ) -- ... % )
over [ count ] [ length ] bi* / ; inline
+: sequence-index-operator-last ( n seq quot -- n quot' )
+ [ [ nth-unsafe ] curry [ keep ] curry ] dip compose ; inline
+
+: find-last-index-from ( ... n seq quot: ( ... elt i -- ... ? ) -- ... i elt )
+ '[
+ _ [ sequence-index-operator-last find-last-integer ] keepd
+ index/element
+ ] bounds-check-call ; inline
+
: find-last-index ( ... seq quot: ( ... elt i -- ... ? ) -- ... i elt )
- [ [ 1 - ] dip find-last-integer ] (find-index) ; inline
+ [ index-of-last ] dip find-last-index-from ; inline
: map-find-last-index ( ... seq quot: ( ... elt index -- ... result/f ) -- ... result i elt )
[ find-last-index ] (map-find-index) ; inline
-:: (start-all) ( subseq seq increment -- indices )
+:: (start-all) ( seq subseq increment -- indices )
0
- [ [ subseq seq ] dip subseq-start-from dup ]
+ [ seq subseq subseq-index-from dup ]
[ [ increment + ] keep ] produce nip ;
-: start-all ( subseq seq -- indices )
- over length (start-all) ; inline
+: start-all ( seq subseq -- indices )
+ dup length (start-all) ; inline
-: start-all* ( subseq seq -- indices )
+: start-all* ( seq subseq -- indices )
1 (start-all) ; inline
-: count-subseq ( subseq seq -- n )
+: count-subseq ( seq subseq -- n )
start-all length ; inline
-: count-subseq* ( subseq seq -- n )
+: count-subseq* ( seq subseq -- n )
start-all* length ; inline
: assoc-zip-with ( quot: ( key value -- calc ) -- alist )
[ dup length ] unless* tail-slice ; inline
: count-head ( seq quot -- n )
- [ not ] compose [ find drop ] 2keep drop length or ; inline
+ [ not ] compose [ find drop ] keepd length or ; inline
: count-tail ( seq quot -- n )
- [ not ] compose [ find-last drop ] 2keep drop
+ [ not ] compose [ find-last drop ] keepd
length swap [ - 1 - ] when* ; inline
+:: shorten* ( vector n -- seq )
+ vector n tail
+ n vector shorten ;
+
:: interleaved-as ( seq glue exemplar -- newseq )
seq length dup 1 - + 0 max exemplar new-sequence :> newseq
seq [ 2 * newseq set-nth-unsafe ] each-index
: find-pred-loop ( ... i n seq quot: ( ... elt -- ... calc ? ) -- ... calc/f i/f elt/f )
2pick < [
[ nipd call ] 4keep
- 7 nrot 7 nrot 7 nrot
+ 3 7 0 nrotated
[ [ 3drop ] 2dip rot ]
[ 2drop [ 1 + ] 3dip find-pred-loop ] if
] [
[ 0 ] 3dip
[ [ length check-length ] keep ] 2dip
'[ nth-unsafe _ keep swap _ keep swap ] find-pred-loop swapd ; inline
+
+! https://en.wikipedia.org/wiki/Maximum_subarray_problem
+! Kadane's algorithm O(n) largest sum in subarray
+: max-subarray-sum ( seq -- sum )
+ [ -1/0. 0 ] dip
+ [ [ + ] keep max [ max ] keep ] each drop ;
+
+TUPLE: step-slice
+ { from integer read-only initial: 0 }
+ { to integer read-only initial: 0 }
+ { seq read-only }
+ { step integer read-only } ;
+
+:: <step-slice> ( from to step seq -- step-slice )
+ step zero? [ "can't be zero" throw ] when
+ seq length :> len
+ step 0 > [
+ from [ 0 ] unless*
+ to [ len ] unless*
+ ] [
+ from [ len ] unless*
+ to [ 0 ] unless*
+ ] if
+ [ dup 0 < [ len + ] when 0 len clamp ] bi@
+ ! FIXME: make this work with steps
+ seq dup slice? [ collapse-slice ] when
+ step step-slice boa ;
+
+M: step-slice virtual-exemplar seq>> ; inline
+
+M: step-slice virtual@
+ [ step>> * ] [ from>> + ] [ seq>> ] tri ; inline
+
+M: step-slice length
+ [ to>> ] [ from>> - ] [ step>> ] tri
+ dup 0 < [ [ neg 0 max ] dip neg ] when /mod
+ zero? [ 1 + ] unless ; inline
+
+INSTANCE: step-slice virtual-sequence
projects / factor.git / blobdiff