Your problem with deal is easily dealt (!) with:
The vocabulary entry for dyadic ?, "deal" is
"x ? yis a list ofxitems randomly chosen/without repetition/fromi.y"
So in particular, 5?5 is a random permutation of i.5 .
The way to get what I think you want is
?10#5 NB. eg roll 10 5-sided dice
4 2 0 0 2 0 3 1 4 1
Though why you should want to generate ips when you
have so many already escapes me!
As for "pip" etc, you _can_ use 32-bit integers in this fashion:
NB. encode, ie shift the 4 elements left 3 2 1 0 bytes
24 16 8 0 +/@:(33 b.) 148 99 57 121
_1805436551
NB. you presumably need to be able to recover the input
NB. so you need this
mask =: 24 16 8 0 (33 b.) 255
NB. to decode, ie unpack the 32-bit integer
_24 _16 _8 0 (33 b.) mask (17 b.) _1805436551
148 99 57 121
This is sort of equivalent to pip:
pip '148.99.57.121'
2489530745
x:1805436551 + 2489530745
4294967296
2x^32
4294967296
If you're content to use such integers, you might find
some more improvement by avoiding the use of extended
integers.
It's surely surprising that J significantly outperforms K .
Have you asked the K-gurus what they think, in the k4
forum?
Mike
On 14/12/2011 10:14 AM, Alexander Epifanov wrote:
> Hello again,
> Here my optimized version with ints, its 1.5 faster then float solution.
> http://dl.dropbox.com/u/34917039/ip.j
>
> The main thing: it is much faster than K!
>
> Could you let me know, is it possible to optimize time of "f" function?
> I tryed to represent IP like 4 ints: 192 168 1 1, but this solution
> works much slower.
>
> ips.txt: file with ip addresses
> ipr.txt: file with ip ranges: ip,ip
>
> And the other thing I cannot understand:
> 5?5
> 4 1 0 2 3
> 10?5
> |domain error
> | 10 ?5
> ???
>
> Thank you,
>
>
[snipped the rest]
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