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<p class="MsoNormal"><span style="font-size:13.0pt">Hi All,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:13.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:13.0pt">I've run into a situation where the binary representation of base 10 numbers is catching up to us for a very small percentage of our students. To illustrate this I've created a public problem demonstrating
the issue. Unlike the problems the students get this one, for the sake of demonstration, walks you through the calculations but uses the exact same numbers that one of our students had to work with resulting in a case where what should be zero is not equal
to zero. What's the best way of preventing this from happening? (The source code is open also in case you want to have a look but it's pretty well spelled out in the problem itself for demonstration purposes).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:13.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:13.0pt"><a href="https://access3.lon-capa.illinois.edu/res/uiuc/dmills/scratchwork/FloatingPointIssueDemo.problem">https://access3.lon-capa.illinois.edu/res/uiuc/dmills/scratchwork/FloatingPointIssueDemo.problem</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:13.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:13.0pt">Thanks in advance and, on that topic, Happy Thanksgiving!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:13.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:13.0pt;color:#13294B">Doug<span style="text-transform:uppercase"><o:p></o:p></span></span></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;color:#13294B;text-transform:uppercase"><o:p> </o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;color:#13294B;text-transform:uppercase">DOUGLAS G MILLS</span></b><span style="font-size:11.0pt;color:black"><br>
</span><i><span style="font-size:11.0pt;color:#13294B">Director of Instructional Technology</span></i><span style="font-size:11.0pt;color:black"><br>
<br>
</span><span style="font-size:11.0pt;color:#13294B">Department of Chemistry</span><span style="font-size:11.0pt;color:black"><br>
<br>
</span><span style="font-size:11.0pt;color:#13294B">University of Illinois at Urbana-Champaign</span><span style="font-size:11.0pt;color:black"><br>
</span><span style="font-size:11.0pt;color:#13294B">Chemistry Annex Box A2</span><span style="font-size:11.0pt;color:black"><br>
</span><span style="font-size:11.0pt;color:#13294B">601 S. Mathews | M/C 712</span><span style="font-size:11.0pt;color:black"><br>
</span><span style="font-size:11.0pt;color:#13294B">Urbana, IL 61801</span><span style="font-size:11.0pt;color:black"><br>
</span><span style="font-size:11.0pt;color:#13294B">217.244.5739 | <i>fax</i>: 217.244.8029 | </span><span style="font-size:11.0pt"><a href="mailto:dmills@illinois.edu"><span style="color:#0563C1">dmills@illinois.edu</span></a><span style="color:black"><br>
</span><span style="color:#13294B"><a href="http://chemistry.illinois.edu"><span style="color:#0563C1">chemistry.illinois.edu</span></a></span><span style="color:black"><br>
<br>
</span></span><a href="http://illinois.edu/"><span style="font-size:11.0pt;color:windowtext;text-decoration:none"><img border="0" width="119" height="21" style="width:1.2395in;height:.2187in" id="Picture_x0020_1" src="cid:image001.png@01D5A471.E5B12830" alt="/var/folders/kv/f3wpy1cs51521x5grm_qx4tw0000gn/T/com.microsoft.Outlook/WebArchiveCopyPasteTempFiles/P698ojxP4tc7j8gMqgPv+E4KQAAAABJRU5ErkJggg=="></span></a><span style="font-size:11.0pt;color:black"><br>
<br>
</span><i><span style="font-size:11.0pt;color:#666666">Under the Illinois Freedom of Information Act any written communication to or from university employees regarding university business is a public record and may be subject to public disclosure. </span></i><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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