I think I'm missing something...
Raul said: "Do we have no way of performing the insertion in the same
order as the evaluation order? This would be important in constructing
efficient gerund scans."
There are only two ways to alternatively insert operators in a
sequence of numbers:
1*2+3*4+5*6+7
209
1+2*3+4*5+6*7
383
The gerund insert allows inserting the verbs either way:
*`+/ 1 2 3 4 5 6 7
209
+`*/ 1 2 3 4 5 6 7
383
Reversing the order of the gerund has the identical effect as
right-to-left insertion:
The order that you insert the verbs in the vector shouldn't matter,
since the execution occurs after all insertions.
What am I missing?
Skip
Skip Cave
Cave Consulting LLC
On Mon, Feb 22, 2016 at 11:38 PM, Raul Miller <[email protected]> wrote:
> Ok, so we left to right insertion combined with right to left
> evaluation. That might be "algorithmically interesting" but it also
> seems unnecessarily complex for some useful cases.
>
> Do we have no way of performing the insertion in the same order as the
> evaluation order? This would be important in constructing efficient
> gerund scans.
>
> And, currently, I'm not seeing any such option - given left to right
> insertion, we would need left to right evaluation of the insertion for
> an efficient scan.
>
> Argh...
>
> --
> Raul
>
>
> On Mon, Feb 22, 2016 at 11:54 PM, bill lam <[email protected]> wrote:
>> In DOJ, but inside Introduction part
>>
>> http://www.jsoftware.com/help/dictionary/intro21.htm
>>
>> to recap,
>> x=.4
>>
>> +`*/1,x,3,x,3,x,1
>> 125
>> 1 + x * 3 + x * 3 + x * 1
>> 125
>> 1 * x + 3 * x + 3 * x + 1
>> 61
>>
>>
>> Пн, 22 фев 2016, Raul Miller написал(а):
>>> http://www.jsoftware.com/help/dictionary/d420.htm says:
>>>
>>> m/y inserts successive verbs from the gerund m between items of y,
>>> extending m cyclically as required. Thus, +`*/i.6 is 0+1*2+3*4+5
>>>
>>> But it does not include an example of m/y where y contains an odd
>>> number of elements.
>>>
>>> From the description, I would expect +`*/3 4 5 to give the result 3*4+5
>>>
>>> However:
>>> 3*4+5
>>> 27
>>> +`*/3 4 5
>>> 23
>>>
>>> I'm thinking that this might be a bug in the interpreter.
>>>
>>> Is there some application, though, that requires the current behavior?
>>>
>>> Thanks,
>>>
>>> --
>>> Raul
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>>
>> --
>> regards,
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