Re: [q-lang-users] Problem using function "isprime"

[Tim H. <q...@st...>]

Dr....@t-... (Albert Graef) writes:

[snip]
> Here's a suitable definition which you can add to your program, copied
> straight from the docs:
[snip]

While we're here, consider this pair of mutually-recursive functions for
the job, as well:

    isprime N = not (any ((=0).(N mod))) (primes (intsqrt N)) ;

    primes N = [2] if  N=2;
             = filter isprime [2..N] otherwise;

Not quite as pretty to look at, but I think it may run faster as it only
uses the primes between 2..intsqrt N rather than all odds, if I read your
algorithm right...

HTH,

~Tim
-- 
<http://spodzone.org.uk/>