The point is I WANT to use special code for my global variables.

> On Apr 26, 2017, at 9:25 AM, Raul Miller <[email protected]> wrote:
> 
> That's because of special code
> http://www.jsoftware.com/help/release/amipcommute.htm and how it
> interacts with the ref count. (You do not want to be doing an in-place
> modification of an array which has multiple references to it.)
> 
> Thanks,
> 
> -- 
> Raul
> 
> 
> On Wed, Apr 26, 2017 at 10:08 AM, Xiao-Yong Jin <[email protected]> wrote:
>>   f=:4 :'y 0}x'
>>   a=:1e6?@#0
>>   timespacex'a=:a f 0'
>> 0.004784 8.39053e6
>>   timespacex'a=:a 0}~0'
>> 8e_6 1920
>> 
>>> On Apr 25, 2017, at 10:35 PM, Raul Miller <[email protected]> wrote:
>>> 
>>> What do you mean by "extra copies" and how have you been measuring that?
>>> 
>>> (Most of the time, a "copy" just means incrementing a reference count.
>>> There have been some exceptions, though, for boxed data, for example.)
>>> 
>>> Thanks,
>>> 
>>> --
>>> Raul
>>> 
>>> 
>>> On Tue, Apr 25, 2017 at 9:19 PM, Xiao-Yong Jin <[email protected]> 
>>> wrote:
>>>> 
>>>>> On Apr 25, 2017, at 6:30 PM, Eric Iverson <[email protected]> 
>>>>> wrote:
>>>>> 
>>>>> I have not followed this discussion at all and am probably way off base.
>>>>> 
>>>>> But how is:
>>>>> 
>>>>> allocate a few structures, and pass their pointers to the same function in
>>>>> separate callings
>>>>> 
>>>>> different from:
>>>>> 
>>>>> allocated a few globals in an agreed upon locale (call it the heap),  and
>>>>> pass their names (pointers) to the same verb in separate callings
>>>>> 
>>>>> ?
>>>> 
>>>> This question is actually right on spot, and I am struggling with this.
>>>> There are two aspects of this problem in my opinion.
>>>> 
>>>> 1. Unnecessary copying of data, given the current state of the in-place
>>>> operations in J.  To have a varied state in J, passing names to verb
>>>> essentially amounts to the following operations,
>>>> 
>>>>  State =. State Verb Control   NB. akin to usual functional style
>>>> 
>>>> Most of the time J would make unnecessary copies of the data in State.
>>>> I haven't found a reliable way to avoid extra copying, except for when
>>>> the 'Verb' here is a primitive.
>>>> 
>>>> 2. Inconvenience, if you want to maintain a set of inhomogeneous states.
>>>> I can do
>>>> 
>>>>  'State1A State1B State1C' = (State1A;State1B;State1C) Verb Control
>>>>  'State2A State2B State2C' = (State2A;State2B;State2C) Verb Control
>>>> 
>>>> Apart from copying/boxing, there are too many names to keep track of.
>>>> I would rather do
>>>> 
>>>>  Verb_1_ Control
>>>>  Verb_2_ Control
>>>> 
>>>> I guess I'm just more familiar with the latter, because it resembles
>>>> a common C function:
>>>> 
>>>>  void Verb(*Locale, const *Control)
>>>> 
>>>> Maybe I'm missing something in J.  Please feel free to correct me.
>>>> 
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