I did not reed your specs well enough and you did not read my outcome well
enough:
   (([EMAIL PROTECTED]&.(p:^:_1)@>: >./@: (<.&.^.) ])"0 -: _4&p:) 160+i.20
0

If I understand you correctly, you want the next odd prime power (including
power 1) greater or equal than the input. Is that right?

R.E. Boss


-----Oorspronkelijk bericht-----
Van: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] Namens Yuvaraj Athur Raghuvir
Verzonden: donderdag 21 september 2006 11:54
Aan: Programming forum
Onderwerp: Re: [Jprogramming] Explicit to Tacit - newbie question

Gotcha!

([EMAIL PROTECTED]&.(p:^:_1)@>: >./@: (<.&.^.) ])"0[ 25
23
   fpp 25
25 25 2 5 2

which means that fpp does the following
a) if input is prime -> return prime
b) if not, find if it is a prime power -> return the base prime and the
power
c) if not keep incrementing (only odd numbers considered) -> until (a) or
(b) is satisfied.

Question was if (b) & (c) can be programmed tacitly.

As it stands, your solution of finding the nearest prime is already
available as a library function _4 p:
   _4 p: 25
23
   _4 p: 25 + i.20
23 23 23 23 23 29 29 31 31 31 31 31 31 37 37 37 37 41 41 43
   _4 p: 160+i.20
157 157 157 157 163 163 163 163 167 167 167 167 167 167 173 173 173 173 173
173

Regards,
Yuva



On 9/21/06, R.E. Boss <[EMAIL PROTECTED]> wrote:
>
>    ([EMAIL PROTECTED]&.(p:^:_1)@>: >./@([^ <[EMAIL PROTECTED]) ])"0[160+i.20
> 157 157 157 163 163 163 163 167 167 169 169 169 169 173 173 173 173 173
> 173
> 179
>
> [EMAIL PROTECTED]&.(p:^:_1)@>:      NB. Hui's solution, excluding the first 
> (2)
> <[EMAIL PROTECTED]                           NB. floor of prime log y
> >./@([^ <[EMAIL PROTECTED])          NB. maximum of prime ^ floor of prime ^. 
> >y
>
> Since ^. and ^ are inverse of each other it can be reformulated to
>
>    ([EMAIL PROTECTED]&.(p:^:_1)@>: >./@: (<.&.^.) ])"0[160+i.20
> 157 157 157 163 163 163 163 167 167 167 167 167 167 173 173 173 173 173
> 173
> 179
>
>
> R.E. BOSS
>


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