Two defns that use only the monad q:
fac1=: , @ > @ (*/&.>/) @ (<@(1,*/\)/.~) @ q:
fac2=: */"1 @ (>@,) @ { @ (<@(1,*/\)/.~) @ q:
----- Original Message -----
From: Roger Hui <[EMAIL PROTECTED]>
Date: Monday, January 7, 2008 8:24
Subject: Re: [Jprogramming] Fitting factors of positive integers
To: Programming forum <[email protected]>
> f=: */ .^"1 (#: i.@(*/))@:>:
> factors=: f/@(__&q:)
>
> factors 160
> 1 5 2 10 4 20 8 40 16 80 32 160
> factors 144
> 1 3 9 2 6 18 4 12 36 8 24 72 16 48 144
> factors 97
> 1 97
> factors 1
> 1
>
> Or, to name a well-known subexpression used therein,
> odometer=: #: i.@(*/)
> f=: */ .^"1 odometer@:>:
>
>
>
> ----- Original Message -----
> From: neville holmes <[EMAIL PROTECTED]>
> Date: Sunday, January 6, 2008 21:12
> Subject: [Jprogramming] Fitting factors of positive integers
> To: [email protected]
>
> > I was trying to put myself to sleep last night by
> > working out (tacit) ways to list the distinct factors
> > of positive integers. Is there a better way than
> > simply sieving through all the candidates less
> > than or equal to the square root of the number ?
> ...
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