Try also:
t2 =: {. -: -...@[ {. ]
a =: 1 2 3 4 1 2 3 4
2 3 4 t2"0 1 a
0 0 1
It works like this:
3{.a
1 2 3
_3{.a
2 3 4
(4{.a) -: _4{.a
1
4 t2 a
1
2 4 t2"0 1 (1 2 3 4 1 2 3 4)
0 1
2 4 t2"0 1 ] 1 2 3 4 1 2 3 4
0 1
unigee wrote:
>
> Hi
>
> I seem to be having a bit of trouble performing this idea.
>
> I am trying to get a subset of a list, and comparing the first element
> against the last element of the result.
>
>
> 2 >\/ (1 2 3 4 1 2 3 4)
> 1 2
> 2 3
> 3 4
> 4 1
> 1 2
> 2 3
> 3 4
>
> t1 =: 4 : '(_1{a) -: (0{ a=. y >\/ (x))'
> 1 2 3 4 1 2 3 4 t1 2
> 0
>
>
> 4 >\/ (1 2 3 4 1 2 3 4)
> 1 2 3 4
> 2 3 4 1
> 3 4 1 2
> 4 1 2 3
> 1 2 3 4
>
> 1 2 3 4 1 2 3 4 t1 4
> 1
>
> t1 works as intended, but I am having trouble making it work with more
> than one right argument at a time
> Here are my failed attempts.
>
> 1 2 3 4 1 2 3 4 t1 2 3 4 NB. result should be 0 0 1
> 0
>
> 1 2 3 4 1 2 3 4 t1"0 2 3 4
> |length error
> | 1 2 3 4 1 2 3 4 t1"0 2 3 4
>
> 1 2 3 4 1 2 3 4 t1 each (2 3 4)
> |length error
> | 1 2 3 4 1 2 3 4 t1 each(2 3 4)
>
> (1 2 3 4 1 2 3 4) t1"0 (2 3 4)
> |length error
> | (1 2 3 4 1 2 3 4) t1"0(2 3 4)
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
>
>
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