It's a problem of integer arithmetic and changing bases: http://docs.sun.com/source/806-3568/ncg_goldberg.html for the details. For a quick idea, try this:

$ perl -e 'printf "%.20f\n",(0.3-0.1)*10'
1.99999999999999977796

[download]
print pack("A25",pack("V*",map{1919242272+$_}(34481450,-49737472,6228,0,-285028276,6979,-1380265972)))

In reply to Re: An arithmetic oddity by bv
in thread An arithmetic oddity by jxb

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