Source PostScript (quicksort.pps)

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%% src : http://www.math.ubc.ca/~cass/graphics/text/www/code/sort.inc %% code de Bill Casselman, modifie par jpv, 18/10/2007 /qsortdict 8 dict def qsortdict begin % args: /comp a L R x % effect: effects a partition into two pieces [L j] [i R] % leaves i j on stack /partition { 8 dict begin /x exch def /j exch def /i exch def /a exch def load /comp exch def { { a i get x comp exec not { exit } if /i i 1 add def } loop { x a j get comp exec not { exit } if /j j 1 sub def } loop i j le { % swap a[i] a[j] a j a i get a i a j get put put indices j indices i get indices i indices j get put put /i i 1 add def /j j 1 sub def } if i j gt { exit } if } loop i j end } def % args: /comp a L R % effect: sorts a[L .. R] according to comp /subsort { % /c a L R [ 3 1 roll ] 3 copy % /c a [L R] /c a [L R] aload aload pop % /c a [L R] /c a L R L R add 2 idiv % /c a [L R] /c a L R (L+R)/2 3 index exch get % /c a [L R] /c a L R x partition % /c a [L R] i j % if j > L subsort(a, L, j) dup % /c a [L R] i j j 3 index 0 get gt { % /c a [L R] i j 5 copy % /c a [L R] i j /c a [L R] i j exch pop % /c a [L R] i j /c a [L R] j exch 0 get exch % ... /c a L j subsort } if % /c a [L R] i j pop dup % /c a [L R] i i % if i < R subsort(a, i, R) 2 index 1 get lt { % /c a [L R] i exch 1 get % /c a i R subsort }{ 4 { pop } repeat } ifelse } def end % args: /comp a % effect: sorts the array a % comp returns truth of x < y for entries in a /quicksort { qsortdict begin dup length 1 gt { % /comp a dup % /comp a a length 1 sub % /comp a n-1 0 exch subsort } { pop pop } ifelse end } def % ---------------------------------------- %% fin du code de Bill Casselman %% syntaxe : array1 doublebubblesort --> array2 array3, array3 est %% trie par ordre croissant et array2 correspond a la position des %% indices de depart, ie si array1 = [3 2 4 1], alors array2 = [3 1 0 2] %% code de Bill Casselman, modifie par jpv, 18/10/2007 %% http://www.math.ubc.ca/people/faculty/cass/graphics/text/www/ /doublequicksort { qsortdict begin /comp exch /a exch def a dup length /n exch def /indices [0 1 n 1 sub {} for ] def dup length 1 gt { % /comp a dup % /comp a a length 1 sub % /comp a n-1 0 exch subsort } { pop pop } ifelse indices a end } def /comp {lt} def