<div dir="ltr">I&#39;m not sure how CReal implements its values, but IEEE754 also supports decimal formats preferred for accuracy in many applications. Take a look:<div><br></div><div>   <a href="http://en.wikipedia.org/wiki/IEEE_floating_point">http://en.wikipedia.org/wiki/IEEE_floating_point</a><br>
</div><div><br></div><div><br></div><div style>Cheers,</div><div style>d</div><div style><br></div><div><br></div></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Tue, Feb 5, 2013 at 3:24 PM, Patrick Mylund Nielsen <span dir="ltr">&lt;<a href="mailto:haskell@patrickmylund.com" target="_blank">haskell@patrickmylund.com</a>&gt;</span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><a href="http://floating-point-gui.de/" target="_blank">http://floating-point-gui.de/</a><div><a href="http://floating-point-gui.de/formats/fp/" target="_blank">http://floating-point-gui.de/formats/fp/</a><br>
<div><br></div><div><a href="http://en.wikipedia.org/wiki/Floating_point#Accuracy_problems" target="_blank">http://en.wikipedia.org/wiki/Floating_point#Accuracy_problems</a><br>
</div></div></div><div class="HOEnZb"><div class="h5"><div class="gmail_extra"><br><br><div class="gmail_quote">On Wed, Feb 6, 2013 at 12:08 AM, KC <span dir="ltr">&lt;<a href="mailto:kc1956@gmail.com" target="_blank">kc1956@gmail.com</a>&gt;</span> wrote:<br>

<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">0.1 cannot be represented exactly in floating point.<br>
<br>
0.5 can be represented exactly.  Why?<br>
<div><br>
<br>
On Tue, Feb 5, 2013 at 2:41 PM, yi lu &lt;<a href="mailto:zhiwudazhanjiangshi@gmail.com" target="_blank">zhiwudazhanjiangshi@gmail.com</a>&gt; wrote:<br>
</div><div><div>&gt; Hi,<br>
&gt;<br>
&gt; I found that in ghci, I input<br>
&gt; [0.1,0.2..2]<br>
&gt; and run, I get a result of<br>
&gt;<br>
&gt; [0.1,0.2,0.30000000000000004,0.4000000000000001,0.5000000000000001,0.6000000000000001,0.7000000000000001,0.8,0.9,1.0,1.1,1.2000000000000002,1.3000000000000003,1.4000000000000004,1.5000000000000004,1.6000000000000005,1.7000000000000006,1.8000000000000007,1.9000000000000008,2.000000000000001]<br>


&gt;<br>
&gt; But, as you know, it is not the exact answer.<br>
&gt;<br>
&gt; So, I wonder if there is something I can do to achieve a better performance<br>
&gt; and get [0.1,0.2,0.3,0.4..] as the result.<br>
&gt;<br>
&gt; Thanks.<br>
&gt;<br>
</div></div><div>&gt; _______________________________________________<br>
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&gt;<br>
<br>
<br>
<br>
</div><span><font color="#888888">--<br>
--<br>
Regards,<br>
KC<br>
</font></span><div><div><br>
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