On 5/22/07, Terrence Brannon <[EMAIL PROTECTED]> wrote:
Raul Miller <rauldmiller <at> gmail.com> writes:
> You mean like this?
> A ( [: > process_prime~&.>/ <"0 @ |. @ ] , < @ [) 2}.i.28
Once again, you have completely out-classed me. I will need to do
some serious head-scratching before I understand what you are doing.
Well... first off, I goofed. I didn't test the code (I did this
without definitions
for A and process_prime). I think this should work though:
A ([: > [: process_prime~&.>/ <"0@|[EMAIL PROTECTED] , <@[) 2}.i.28
Second off, if something is confusing, looking at the data usually helps.
For example, cutting the inner train, two verbs at a time, until I get rid
of process_prime:
A ( [: process_prime~&.>/ <"0@|[EMAIL PROTECTED] , <@[) 2}.i.28
A (<"0@|[EMAIL PROTECTED] , <@[) 2}.i.28
And, substituting an arbitrary value for A:
'A' (<"0@|[EMAIL PROTECTED] , <@[) 2}.i.28
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+-+-+-+-+-+-+-+-+-+
|27|26|25|24|23|22|21|20|19|18|17|16|15|14|13|12|11|10|9|8|7|6|5|4|3|2|A|
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+-+-+-+-+-+-+-+-+-+
Basically, I've put each of the arguments in boxes, and arranged them
so a right-to-left scan will process them in the right order. Note also
that I'm using
process_prime~&.>/
Here's how those adverbs kick in:
/ process the data in from right to left, using the dyad:
&.> which works inside the boxes with the dyad:
~ swapping left and right arguments with the dyad: process_prime
Once that's all done, my result is in a box, I have to unbox it for the
final result.
I hope this helps (and I hope I did not make any other mistakes).
here is the algorithm - http://www.nist.gov/dads/HTML/sieve.html
With that specification, I'd be tempted to implement it as:
sieve=:3 :0
r=.(y+1){.1 1
for_prime.i.&.(p:inv)y do.
r=.1 ((prime*}.>:i.y<[EMAIL PROTECTED]))} r
end.
r
)
Or, tacitly, ... nah, I don't want to overwhelm you (but the basic technique
is the same one I illustrated above -- using &.>/
Of course, I'm being a bit silly, but I guess that's because I feel the
concept is a bit silly.
--
Raul
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