Re: [Jprogramming] Partitions

[Linda Alvord]

Maybe you will find comb2 interesfing.

load 'stats'

comb2=:([ = [: +/"1 [: #: [: i. 2 ^ ]) ([: |. [: I. #) [: #: [: i. 2 ^ ]

(4 comb2 7)-:4 comb 7


Li nda



Get Outlook for Android<https://aka.ms/ghei36>

________________________________
From: Programming <programming-boun...@forums.jsoftware.com> on behalf of 
Erling Hellenäs <erl...@erlinghellenas.se>
Sent: Wednesday, November 1, 2017 7:13:33 AM
To: programm...@jsoftware.com
Subject: Re: [Jprogramming] Partitions

Hi all!

parRuskey comparison.

Mike Days new version is slightly faster than the Frank Ruskey version.

Cheers,

Erling Hellenäs

----------Project----------

ts=: 6!:2 , 7!:2@]       NB. Time and space

normalize=: 3 :0
NB. The idea here is to normalize the representation so that
NB. the copies are adjacent.
NB. Sort buckets within each combination after first item in each bucket
v31=.(] /: {.&.>)"1 y
NB. Sort buckets within each combination after number of items in each
bucket
v4=.(] /: #&.>)"1 v31
NB. Sort
v5=. /:~  v4
(/: #&.> v5){ v5
)

compare=: -:&:normalize

NB. parELMDE for comparison

parELMDE=: 4 : 0
a =. ~. i.~"1 iy #: i. */ iy =. (1+i.x),(y-x)$x
a =. a#~ x = #@~."1 a
sort a </."1 i. y
)

NB. Original Frank Ruskey version.

parRuskey =: 4 : 0
a=: i. y
r=: (0,y)$0
(x-1) S y-1
r </."1 i.y
)


S =: 4 : 0
if. x=y do.
   r=:r,a
else.
   for_i. i.x+1 do.
     a=: i y } a
     x S y-1
     a=: y y } a
   end.
   if. x > 0 do.
     a=: x y } a
     (x-1) S y-1
     a=: y y } a
   end.
end.
)

NB. Slightly modified by Erling to remove global variables.

parRuskeyE =: 4 : 0
r=. (i.y) SE (x-1);y-1
r </."1 i.y
)

SE =: 4 : 0
'k n' =. y
r=. 0{.,:x
if. k=n do.
   r=.,:x
else.
   for_i. i.k+1 do.
     r=.r, (i n } x) SE k;n-1
end.
   if. k > 0 do.
     r=.r, (k n } x) SE (k-1);n-1
   end.
end.
r
)

NB. Modified by Mike Day

parRuskeyMD =: 4 : 0
NB. L =: 0$~0, 2 + y   NB. debug/understand array of call parameters
r=. (i.y) SMD (x-1),y-1
NB. R =: r             NB. debug/understand output
r </."1 i.y
)

SMD =: 4 : 0
NB. L =: L, y, x       NB. debug/understand array of call parameters
'k n' =. y
a =.x
r =. 0$~ 0, #a
if. k = n - 1 do.      NB. replace repeated calls with k = n (on entry)
   r =. (i.k+1) n }"0 1 (k+1)# ,:a  NB. don't need to use recursion here!
else.
      NB. is there a way to avoid recursion here,  too?
   r =. r, ,/ (SMD&(k,n-1))"1 (i.k+1) n }"0 1 a NB.apply "1 instead of
do loop
end.
if. k > 0 do.
   r=.r, (k n } a) SMD (k-1),n-1
end.
r
)

x=:1
y=:1
(x parELMDE y) compare x parRuskey y
(x parELMDE y) compare x parRuskeyE y
NB.(x parELMDE y) compare x parRuskeyMD y - Error
x=:1
y=:2
(x parELMDE y) compare x parRuskey y
(x parELMDE y) compare x parRuskeyE y
(x parELMDE y) compare x parRuskeyMD y
x=:2
y=:3
(x parELMDE y) compare x parRuskey y
(x parELMDE y) compare x parRuskeyE y
(x parELMDE y) compare x parRuskeyMD y
x=:3
y=:5
(x parELMDE y) compare x parRuskey y
(x parELMDE y) compare x parRuskeyE y
(x parELMDE y) compare x parRuskeyMD y
x=:3
y=:6
(x parELMDE y) compare x parRuskey y
(x parELMDE y) compare x parRuskeyE y
(x parELMDE y) compare x parRuskeyMD y

x=:5
y=:10
ts'x parRuskey y'
ts'x parRuskeyE y'
ts'x parRuskeyMD y'


-------Output-------------------


    x=:1
    y=:1
    (x parELMDE y) compare x parRuskey y
1
    (x parELMDE y) compare x parRuskeyE y
1
    NB.(x parELMDE y) compare x parRuskeyMD y - Error
    x=:1
    y=:2
    (x parELMDE y) compare x parRuskey y
1
    (x parELMDE y) compare x parRuskeyE y
1
    (x parELMDE y) compare x parRuskeyMD y
1
    x=:2
    y=:3
    (x parELMDE y) compare x parRuskey y
1
    (x parELMDE y) compare x parRuskeyE y
1
    (x parELMDE y) compare x parRuskeyMD y
1
    x=:3
    y=:5
    (x parELMDE y) compare x parRuskey y
1
    (x parELMDE y) compare x parRuskeyE y
1
    (x parELMDE y) compare x parRuskeyMD y
1
    x=:3
    y=:6
    (x parELMDE y) compare x parRuskey y
1
    (x parELMDE y) compare x parRuskeyE y
1
    (x parELMDE y) compare x parRuskeyMD y
1

    x=:5
    y=:10
    ts'x parRuskey y'
0.204245 3.89459e7
    ts'x parRuskeyE y'
0.316044 3.8954e7
    ts'x parRuskeyMD y'
0.173341 3.8954e7


Cheers,


Erling Hellenäs


Den 2017-10-31 kl. 20:17, skrev 'Mike Day' via Programming:
> parRuskeynew =: 4 : 0
> NB. L =: 0$~0, 2 + y   NB. debug/understand array of call parameters
> r=. (i.y) Snew (x-1),y-1
> NB. R =: r             NB. debug/understand output
> r </."1 i.y
> )
>
> Snew =: 4 : 0
> NB. L =: L, y, x       NB. debug/understand array of call parameters
> 'k n' =. y
> a =.x
> r =. 0$~ 0, #a
> if. k = n - 1 do.      NB. replace repeated calls with k = n (on entry)
>   r =. (i.k+1) n }"0 1 (k+1)# ,:a  NB. don't need to use recursion here!
> else.
>      NB. is there a way to avoid recursion here,  too?
>   r =. r, ,/ (Snew&(k,n-1))"1 (i.k+1) n }"0 1 a NB.apply "1 instead of
> do loop
> end.
> if. k > 0 do.
>   r=.r, (k n } a) Snew (k-1),n-1
> end.
> r
> )

----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm