From: Armando Padilla <mando81@...>
Date: 2007-12-02T02:04:59+09:00
Subject: Re: Float Question

 > I fail to see where the issue with using (s)printf is.

If i use sprintf im assuming that the argument is changed to a string 
type.  If then i chose to calculate additional values with this string 
type i would have to reconvert it to a float.  On the surface its fine, 
i wouldnt mind doing it but I need speed and any less lines that ruby 
will translate too in terms of machine language is beneficial to me.

I actually like Maddox truncate example.  Thanks Maddox. i wasnt aware 
of both that feature and *.format <digit here> Klemme suggested.



Robert Klemme wrote:
> On 01.12.2007 09:26, Armando Padilla wrote:
>> Hey Chris thanks for the feedback.  Yea im using that but i was 
>> looking for something built into the Float stack.
> 
> Class != stack.
> 
>> Something along the lines of Float.new(<number of values after decimal 
>> here>).  Basically something without the need to use sprintf.
> 
> I fail to see where the issue with using (s)printf is.  Anyway, if you 
> do not like the syntax of sprintf you can as well do this:
> 
> irb(main):001:0> f=1.0/3
> => 0.333333333333333
> irb(main):002:0> "%.2f" % f
> => "0.33"
> 
>> Next release of Ruby request?  lol
> 
> Probably not.  As others have demonstrated, you can easily do this in 
> Ruby today.  But it seems, few people know the star operator in printf 
> format strings.  You can do this:
> 
> irb(main):021:0> module Precision
> irb(main):022:1> def format(decimals,total=0)
> irb(main):023:2> sprintf "%*.*f", total, decimals, self
> irb(main):024:2> end
> irb(main):025:1> end
> => nil
> irb(main):026:0> f=1.0/3
> => 0.333333333333333
> irb(main):027:0> f.format 3
> => "0.333"
> irb(main):028:0> f.format 3,10
> => "     0.333"
> 
> Kind regards
> 
>     robert