On 12 March 2011 13:42, Rob Biedenharn <[email protected]> wrote: > > On Mar 12, 2011, at 5:37 AM, Colin Law wrote: > >> On 12 March 2011 10:10, Erwin <[email protected]> wrote: >>> >>> I know how to generate a random number between 1 and 2 : >>> >>> def random >>> return (1 + rand(2))
No it doesn't actually. 1 + rand would be better, though it depends what you mean by *between* whether even that is correct. >>> end >>> >>> but let's say I would like to return 1 in 80% of the calls and 2 in >>> 20% of the call... >>> which library should I use ? ( I've seen a lot at >>> http://raa.ruby-lang.org/ >>> ) >>> >> >> No doubt there are better ways but something like >> (rand(100) + 120)/100 >> should do it. >> >> Colin > > > Well, perhaps something that reveals the intention better: > > def usually_one > rand < 0.80 ? 1 : 2 > end Yes, much better. I suppose it is the old programmer in me instinctively avoiding floating point to save on processor time. A bit silly when everything has hardware floating point. Colin -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
