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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Indeed!&nbsp; Getting the library numerics to do the Right Thing is something
that can only be done by people who know about numerics.&nbsp; People who build
compilers aren&#8217;t, alas.&nbsp; It&#8217;s quite a specialised subject, and very easy to
screw up.&nbsp; And there&#8217;s performance to worry about too in the common case when
the corner cases don&#8217;t appear.<o:p></o:p></span></p>

<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p>&nbsp;</o:p></span></p>

<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>So if there are folk out there who care about getting numerics
correct, we would welcome your direct involvement.&nbsp; Look at the code, make it
right, send patches to <a href="mailto:libraries@haskell.org">libraries@haskell.org</a>.
&nbsp;It&#8217;s all open source, and you&#8217;ll be benefiting lots of people.<o:p></o:p></span></p>

<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p>&nbsp;</o:p></span></p>

<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Simon<o:p></o:p></span></p>

<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p>&nbsp;</o:p></span></p>

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<p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:
"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> haskell-cafe-bounces@haskell.org
[mailto:haskell-cafe-bounces@haskell.org] <b>On Behalf Of </b>Lennart
Augustsson<br>
<b>Sent:</b> 04 August 2007 16:47<br>
<b>To:</b> Andrew Coppin<br>
<b>Cc:</b> haskell-cafe@haskell.org<br>
<b>Subject:</b> Re: [Haskell-cafe] How odd...<o:p></o:p></span></p>

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<p class=MsoNormal><o:p>&nbsp;</o:p></p>

<p class=MsoNormal style='margin-bottom:12.0pt'>Haskell doesn't know much about
infinity, but Haskell implementations are allowed to use IEEE floating point
which has infinity.<br>
And to get things right, there needs to be a few changes to the library to do
the right thing for certain numbers, this is not news.&nbsp; In fact I filed a
bug report a while back about it. <br>
<br>
&nbsp; -- Lennart<o:p></o:p></p>

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<p class=MsoNormal><span class=gmailquote>On 8/4/07, <b>Andrew Coppin</b> &lt;<a
href="mailto:andrewcoppin@btinternet.com">andrewcoppin@btinternet.com</a>&gt;
wrote:</span><o:p></o:p></p>

<p class=MsoNormal>Paul Johnson wrote:<br>
&gt; Andrew Coppin wrote:<br>
&gt;&gt; &gt; 0**2<br>
&gt;&gt; 0<br>
&gt;&gt;<br>
&gt;&gt; &gt; (0 :+ 0)**2<br>
&gt;&gt; NaN :+ NaN<br>
&gt;&gt;<br>
&gt;&gt; (Is this a bug?)<br>
&gt; According to the Standard Prelude, <br>
&gt; #&nbsp;&nbsp; x **
y&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =&nbsp;&nbsp;exp
(log x * y)<br>
<br>
<br>
<o:p></o:p></p>

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<p class=MsoNormal><o:p>&nbsp;</o:p></p>

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