From mboxrd@z Thu Jan  1 00:00:00 1970
From: shot@hot.pl (Shot (Piotr Szotkowski))
Date: Mon, 3 Dec 2007 11:52:10 +0100
Subject: [sup-talk] Util - Fixnum num_digits is wrong
In-Reply-To: <1196670157-sup-6857@silver>
References: <1196670157-sup-6857@silver>
Message-ID: <20071203105210.GO1974@durance.shot.pl>

Ian Taylor:

>  class Fixnum
>    def num_digits base=10
>      return 1 if self == 0
> -    1 + (Math.log(self) / Math.log(10)).floor
> +    1 + (Math.log(self) / Math.log(base)).floor
>    end

Math.log and Float#/ returning Floats means the above
approach is prone to the IEEE 754 representation inaccuracy.

Wouldn?t the below make more sense?

class Fixnum
  def num_digits base = 10
    to_s(base).size
  end
end

-- Shot
-- 
> Who wants to recommend a Usenet reader for little ol' me?
I recommend Garrett Morris, particularly if you're hard-of-hearing.
      -- jennifer friedoff and Joseph Nebus, rec.arts.tv.mst3k.misc
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