<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px"><div id="yiv9730567155"><div id="yui_3_16_0_1_1424805462252_16821"><div id="yui_3_16_0_1_1424805462252_16820" style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px;"><div dir="ltr" id="yiv9730567155yui_3_16_0_1_1424805462252_14259"><span id="yiv9730567155yui_3_16_0_1_1424805462252_14474">While I don't doubt the facts presented below, it just seems wrong, notwithstanding what the standard states.</span></div><div dir="ltr" id="yiv9730567155yui_3_16_0_1_1424805462252_14618"><br clear="none"><span id="yiv9730567155yui_3_16_0_1_1424805462252_14474"></span></div><div dir="ltr" id="yiv9730567155yui_3_16_0_1_1424805462252_14619"><span id="yiv9730567155yui_3_16_0_1_1424805462252_14474">MUMPS (http://en.wikipedia.org/wiki/MUMPS), my workday language for 30-some years, would never think of acting in such a manner:</span></div><div dir="ltr" id="yiv9730567155yui_3_16_0_1_1424805462252_14620"><br clear="none"><span id="yiv9730567155yui_3_16_0_1_1424805462252_14474"></span></div><div dir="ltr" id="yiv9730567155yui_3_16_0_1_1424805462252_14621"><span id="yiv9730567155yui_3_16_0_1_1424805462252_14474">s sum=0 f i=1:1:8 s sum=sum+.1 <br class="yiv9730567155" style="" clear="none"> <br class="yiv9730567155" style="" clear="none">w sum <br class="yiv9730567155" style="" clear="none">.8 <br class="yiv9730567155" style="" clear="none"><br></span></div><div id="yui_3_16_0_1_1424805462252_16874" dir="ltr"><div>I gather, though, that such behavior in other languages is typical, correct?</div></div><div dir="ltr" id="yiv9730567155yui_3_16_0_1_1424805462252_14710"><br clear="none"><span id="yiv9730567155yui_3_16_0_1_1424805462252_14474"></span></div><div dir="ltr" id="yiv9730567155yui_3_16_0_1_1424805462252_14682"><span id="yiv9730567155yui_3_16_0_1_1424805462252_14474">Steve</span></div><br clear="none"> <div class="qtdSeparateBR"><br><br></div><div class="yiv9730567155yqt5015987973" id="yiv9730567155yqt73515"><div id="yiv9730567155yui_3_16_0_1_1424805462252_14200" style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px;"> <div id="yiv9730567155yui_3_16_0_1_1424805462252_14199" style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"> <div dir="ltr" id="yiv9730567155yui_3_16_0_1_1424805462252_14198"> <hr size="1"> <font id="yiv9730567155yui_3_16_0_1_1424805462252_14256" face="Arial" size="2"> <b><span style="font-weight:bold;">From:</span></b> Konrad Hinsen <konrad.hinsen@fastmail.net><br clear="none"> <b><span style="font-weight:bold;">To:</span></b> Laurent <laurent.orseau@gmail.com>; users <users@racket-lang.org> <br clear="none"> <b><span style="font-weight:bold;">Sent:</span></b> Tuesday, February 24, 2015 10:13 AM<br clear="none"> <b><span style="font-weight:bold;">Subject:</span></b> Re: [racket] Inconsistency of `in-range` and numerical issues<br clear="none"> </font> </div> <div class="yiv9730567155y_msg_container" id="yiv9730567155yui_3_16_0_1_1424805462252_14711"><br clear="none">On 24/02/2015 17:04, Laurent wrote:<br clear="none"><br clear="none">> Btw, the reason it outputs 8 in the bad case is because on my machine:<br clear="none">> (for/sum ([i 8]) .1) ; 0.7999999999999999<br clear="none">><br clear="none">> which is then below the .8 threshold.<br clear="none"><br clear="none">It's not just your machine. 0.1 = 1/10 does not have an exact <br clear="none">representation as a binary floating-point number. It gets rounded to the <br clear="none">nearest binary float value, which is smaller than 0.1. This is the <br clear="none">correct behavior according to IEEE 754.<br clear="none"><br clear="none">Konrad.<div class="yiv9730567155qtdSeparateBR"><br clear="none"><br clear="none"></div><div class="yiv9730567155yqt4672870290" id="yiv9730567155yqtfd03807"><br clear="none">____________________<br clear="none"> Racket Users list:<br clear="none"> <a rel="nofollow" shape="rect" target="_blank" href="http://lists.racket-lang.org/users">http://lists.racket-lang.org/users</a><br clear="none"></div><br clear="none"><br clear="none"></div> </div> </div></div> </div></div></div></div></body></html>