factor/basis/grouping/grouping.factor

123 lines
2.8 KiB
Factor

! Copyright (C) 2005, 2010 Slava Pestov, Joe Groff.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors combinators fry kernel math math.order
sequences sequences.private ;
IN: grouping
ERROR: groups-error seq n ;
<PRIVATE
GENERIC: group@ ( n groups -- from to seq )
TUPLE: chunking { seq read-only } { n read-only } ;
INSTANCE: chunking sequence
M: chunking nth-unsafe group@ <slice-unsafe> ; inline
M: chunking set-nth-unsafe group@ <slice-unsafe> 0 swap copy ;
M: chunking like drop { } like ; inline
: check-groups ( seq n -- seq n )
dup 0 <= [ groups-error ] when ; inline
: new-groups ( seq n class -- groups )
[ check-groups ] dip boa ; inline
PRIVATE>
TUPLE: groups < chunking ;
M: groups length
[ seq>> length ] [ n>> ] bi [ + 1 - ] keep /i ; inline
M: groups set-length
[ n>> * ] [ seq>> ] bi set-length ; inline
M: groups group@
[ n>> [ * dup ] keep + ] [ seq>> ] bi [ length min ] keep ; inline
: <groups> ( seq n -- groups )
groups new-groups ; inline
TUPLE: clumps < chunking ;
M: clumps length
dup seq>> length [ drop 0 ] [
swap [ 1 + ] [ n>> ] bi* [-]
] if-zero ; inline
M: clumps set-length
[ n>> + 1 - ] [ seq>> ] bi set-length ; inline
M: clumps group@
[ n>> over + ] [ seq>> ] bi ; inline
: <clumps> ( seq n -- clumps )
clumps new-groups ; inline
<PRIVATE
: map-like ( seq n quot -- seq )
keepd '[ _ like ] map ; inline
PRIVATE>
: group ( seq n -- array ) [ <groups> ] map-like ; inline
: clump ( seq n -- array ) [ <clumps> ] map-like ; inline
: monotonic? ( seq quot: ( elt1 elt2 -- ? ) -- ? )
over length dup 2 < [ 3drop t ] [
2 = [
[ first2-unsafe ] dip call
] [
[ [ first-unsafe 1 ] [ setup-each ] bi ] dip
'[ @ _ keep swap ] (all-integers?) nip
] if
] if ; inline
: all-equal? ( seq -- ? ) [ = ] monotonic? ;
: all-eq? ( seq -- ? ) [ eq? ] monotonic? ;
TUPLE: circular-slice
{ from integer read-only }
{ to integer read-only }
{ seq read-only } ;
INSTANCE: circular-slice virtual-sequence
M: circular-slice equal? over circular-slice? [ sequence= ] [ 2drop f ] if ;
M: circular-slice hashcode* [ sequence-hashcode ] recursive-hashcode ;
M: circular-slice length [ to>> ] [ from>> ] bi - ; inline
M: circular-slice virtual-exemplar seq>> ; inline
M: circular-slice virtual@
[ from>> + ] [ seq>> ] bi [ length rem ] keep ; inline
C: <circular-slice> circular-slice
TUPLE: circular-clumps
{ seq read-only }
{ n read-only } ;
INSTANCE: circular-clumps sequence
M: circular-clumps length
seq>> length ; inline
M: circular-clumps nth
[ n>> over + ] [ seq>> ] bi <circular-slice> ; inline
: <circular-clumps> ( seq n -- clumps )
circular-clumps new-groups ; inline
: circular-clump ( seq n -- array )
[ <circular-clumps> ] map-like ; inline