[Jprogramming] A Tree Question

[Raul Miller]

You can replace @ with a word like at, if you like:

at=:2 :0
  ([: u v)"v
)

-- 
Raul

On Fri, Dec 21, 2012 at 1:30 PM, Linda Alvord <lindaalvord at verizon.net> wrote:
> So how can you write an equivalent explicit expression that will have the same result of g without  @ or @: ?
>
> -----Original Message-----
> From: programming-bounces at forums.jsoftware.com [mailto:programming-bounces at forums.jsoftware.com] On Behalf Of bob therriault
> Sent: Friday, December 21, 2012 1:02 PM
> To: programming at jsoftware.com
> Subject: Re: [Jprogramming] A Tree Question
>
>   Hi LInda,
>
> Since forks result in verbs of infinite rank (unless changed by the rank conjunction), #@# is not actually equivalent to ([:##), although #@:# is. Watch what happens when I swap @: for @
>
>  g=: 13 :'(=x) #@# y'
>    a=:0 0 1 0 1 5
>    b=:0 1 1 3 2 3
>    a g b
> 3 2 1
>    g1=:13 :'(=x) #@:# y'
>    a g1 b
> 3
>
> Cheers, bob
>
> On 2012-12-21, at 9:51 AM, Linda Alvord wrote:
>
>> Why do the trees of  g  and  h appear to agree, but their results are
>> not the same?
>>
>>
>>
>>    ]a=:?>:i.6
>>
>> 0 0 1 0 1 5
>>
>>   ]b=:?>:i.6
>>
>> 0 1 1 3 2 3
>>
>>   f=: 13 :'x#/.y'
>>
>>   f
>>
>> #/.
>>
>>   a f b
>>
>> 3 2 1
>>
>>   g=: 13 :'(=x) #@# y'
>>
>>   g
>>
>> ] #@#~ [: = [
>>
>>   a g b
>>
>> 3 2 1
>>
>>   NB. x u at v y ↔ u x v y
>>
>>   h=: 13 :'(=x) ([:##) y']
>>
>>   h
>>
>> (] ([: # #)~ [: = [) ]
>>
>>   a h b
>>
>> 3
>>
>>   5!:4 <'g'
>>
>>  ┌─ ]
>>  │           ┌─ #
>>  ├─ ~ ─── @ ─┴─ #
>> ──┤
>>  │     ┌─ [:
>>  └─────┼─ =
>>        └─ [
>>
>>   5!:4 <'h'
>>
>>      ┌─ ]
>>      │          ┌─ [:
>>      ├─ ~ ──────┼─ #
>>  ┌───┤          └─ #
>>  │   │     ┌─ [:
>> ──┤   └─────┼─ =
>>  │         └─ [
>>  └─ ]
>>
>>   g
>>
>> ] #@#~ [: = [
>>
>>   h
>>
>> (] ([: # #)~ [: = [) ]
>>
>>
>>
>> Backtracking  i  and  j  are OK.
>>
>>
>>
>>  i=: 13 :'x #@# y'
>>
>>   i
>>
>> #@#
>>
>>   a i b
>>
>> 7
>>
>>   j=: 13 :'#x#y'
>>
>>   j
>>
>> [: # #
>>
>>   a j b
>>
>> 7
>>
>>   5!:4 <'i'
>>
>>      ┌─ #
>> ── @ ─┴─ #
>>
>>   5!:4 <'j'
>>
>>  ┌─ [:
>> ──┼─ #
>>  └─ #
>>
>>
>>
>> I have tried to include rank of the verbs but I haven’t found the
>> right combination if that is what is necessary.
>>
>>
>>
>> Linda
>>
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