From: Michael Morin <uzimonkey@...>
Date: 2008-12-19T11:53:41+09:00
Subject: Re: about Float

Kyung won Cheon wrote:
> a = 1333.3339999999964
> b = 1333.3339999999965
> c = 1333.334
> 
> puts a       # 1333.334
> puts b       # 1333.334
> puts c       # 1333.334
> 
> puts a == b  # => false
> puts a == c  # => false
> puts b == c  # => false
> 
> #########################################################
> # HELP ME^^
> #
> # How can I see 'real value' of Float object(a, b, c) ?
> #########################################################

Comparing floating point numbers is usually not a very good idea. 
They're only approximations of the real number you're trying to 
represent.  For that reason, when printing floating point numbers, it's 
useful to specify with what precision you want to print them.  This 
usually involves some sort of format string.  The sprintf example works, 
but I prefer something like this.

a = 6.232523
puts ("%.3f" % a)

-- 
Michael Morin
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