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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">Hi guys</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">I need to compare two floats something like 0.99999998... vs 1.000000</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">and we came across accuracy problems when testing dihedral angles on a molecule...</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">so we read http://www.cygnus-software.com/papers/comparingfloats/comparingfloats.htm</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">and wanted to implement something like:</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><br /></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" color:#0000ff;">if</span> (*(<span style=" color:#0000ff;">int</span>*)&f1 < *(<span style=" color:#0000ff;">int</span>*)&f2)...</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><br /></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">when ef1 and f2 are floats... (f1 about 0.9999899.. and f2=1.0</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">is think we should start with...</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"> </p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><<Padding:16,Myint:64>> = term_to_binary(1.9999976,[{minor_version,1}]).</p>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><br /></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><br /></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">and let Padding swallow the external format and tag while Myint gets the ieee754 float </p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><br /></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">But MyInt = 4611686017346523993 instead of <span style=" font-family:'Courier New'; font-size:10pt; vertical-align:bottom;">1073741822</span></p>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0; font-family:'Courier New'; font-size:10pt; vertical-align:bottom;"></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt; vertical-align:bottom;">these conversion should follow ieee754 and being lexicografic ordered</span></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt; vertical-align:bottom;">but ...</span></p>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0; font-family:'Courier New'; font-size:10pt; vertical-align:bottom;"></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt; vertical-align:bottom;">term_to_binary(1.99999976,[{minor_version,1}]). </span></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt; vertical-align:bottom;"><<131,70,63,255,255,255,191,147,83,89>></span></p>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0; font-family:'Courier New'; font-size:10pt; vertical-align:bottom;"></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt; vertical-align:bottom;">term_to_binary(1.99999988,[{minor_version,1}]).</span></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt; vertical-align:bottom;"><<131,70,63,255,255,255,223,201,169,173>> </span></p>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0; font-family:'Courier New'; font-size:10pt; vertical-align:bottom;"></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt; vertical-align:bottom;">doesnt seem to be the same thatn you spect to see after reading that page...</span></p>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0; font-family:'Courier New'; font-size:10pt; vertical-align:bottom;"></p>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0; font-family:'Courier New'; font-size:10pt; vertical-align:bottom;"></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt; vertical-align:bottom;">..What im doing wrong....?</span></p>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0; font-family:'Courier New'; font-size:10pt; vertical-align:bottom;"></p>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><br /></p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">ieee754 layout....</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><br /></p>
<table border="0" style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px;" cellspacing="2" cellpadding="0">
<tr>
<td width="155" style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">+1.99999976</span> </p></td>
<td width="108" style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">0x3FFFFFFE</span> </p></td>
<td width="106" style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p align="right" style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">1073741822</span> </p></td></tr>
<tr>
<td style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">+1.99999988</span> </p></td>
<td style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">0x3FFFFFFF</span> </p></td>
<td style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p align="right" style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">1073741823</span> </p></td></tr>
<tr>
<td style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">+2.00000000</span> </p></td>
<td style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">0x40000000</span> </p></td>
<td style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p align="right" style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">1073741824</span> </p></td></tr>
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<td style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">+2.00000024</span> </p></td>
<td style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">0x40000001</span> </p></td>
<td style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p align="right" style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">1073741825</span> </p></td></tr>
<tr>
<td style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">+2.00000048</span> </p></td>
<td style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">0x40000002</span> </p></td>
<td style=" vertical-align:bottom; padding-left:0; padding-right:0; padding-top:0; padding-bottom:0;">
<p align="right" style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;"><span style=" font-family:'Courier New'; font-size:10pt;">1073741826</span></p></td></tr></table>
<p style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">Thanks!..</p>
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<p style=" margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">/Angel </p>
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