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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Effectively it is much better to use isempty() function (or ~isempty() in the current case) … I didn’t know it so far<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Many thanks for your help<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Paul<o:p></o:p></span></p>
<p class="MsoNormal"><o:p></o:p></p>
<p><b><i><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:gray">EXPORT CONTROL :
<br>
</span></i></b><b><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">Cet email ne contient pas de données techniques<br>
This email does not contain technical data</span></b><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><a name="_____replyseparator"></a><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">De :</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Pierre Vuillemin [mailto:contact@pierre-vuillemin.fr]
<br>
<b>Envoyé :</b> jeudi 27 août 2015 13:08<br>
<b>À :</b> Users mailing list for Scilab<br>
<b>Cc :</b> Carrico, Paul<br>
<b>Objet :</b> Re: [Scilab-users] Booeleans : irrelevant results ?<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p><span style="font-size:10.0pt">Dear Paul,<o:p></o:p></span></p>
<p><span style="font-size:10.0pt">The behaviour of test 2 may come from the order in which the operations are performed :<o:p></o:p></span></p>
<p><span style="font-size:10.0pt"> <o:p></o:p></span></p>
<p><span style="font-size:10.0pt">Note that (a & c & b) ~= (b & c & a), indeed :<o:p></o:p></span></p>
<p><span style="font-size:10.0pt">- a & c & b performs a & c which returns [] and then [] & b which returns [],<o:p></o:p></span></p>
<p><span style="font-size:10.0pt">- b & c & a performs b & c which returns %t and then %t & [] which returns %t.<o:p></o:p></span></p>
<p><span style="font-size:10.0pt">You can obtain the desired behaviour by adding parenthesis<o:p></o:p></span></p>
<p><span style="font-size:10.0pt">b & (c & a) returns []<o:p></o:p></span></p>
<p><span style="font-size:10.0pt">but it may be safer to use isempty() to check whether a variable is empty or not.<o:p></o:p></span></p>
<p><span style="font-size:10.0pt"> <o:p></o:p></span></p>
<p><span style="font-size:10.0pt">Best regards,<o:p></o:p></span></p>
<p><span style="font-size:10.0pt"> <o:p></o:p></span></p>
<p><span style="font-size:10.0pt">Pierre<o:p></o:p></span></p>
<p><span style="font-size:10.0pt"> <o:p></o:p></span></p>
<p><span style="font-size:10.0pt">Le 27.08.2015 12:29, Carrico, Paul a écrit :<o:p></o:p></span></p>
<blockquote style="border:none;border-left:solid #1010FF 1.5pt;padding:0cm 0cm 0cm 5.0pt;margin-left:0cm;margin-right:0cm">
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Dear All,<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I wondering what I’m doing wrong in the examples here bellow:<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt"><span style="font-size:10.0pt">-</span><span style="font-size:7.0pt">
</span><span style="font-size:10.0pt">Test 1 </span><span style="font-size:10.0pt;font-family:Wingdings">à</span><span style="font-size:10.0pt"> M returns False that’s ok for me<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt"><span style="font-size:10.0pt">-</span><span style="font-size:7.0pt">
</span><span style="font-size:10.0pt">Test 2 </span><span style="font-size:10.0pt;font-family:Wingdings">à</span><span style="font-size:10.0pt"> should return False as well, shouldn’t be ?<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt"><span style="font-size:10.0pt">-</span><span style="font-size:7.0pt">
</span><span style="font-size:10.0pt">Test 3 </span><span style="font-size:10.0pt;font-family:Wingdings">à</span><span style="font-size:10.0pt"> another test using directly a Boolean instead of an empty form []<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt"><span style="font-size:10.0pt">-</span><span style="font-size:7.0pt">
</span><span style="font-size:10.0pt">Test 4 </span><span style="font-size:10.0pt;font-family:Wingdings">à</span><span style="font-size:10.0pt"> as expected, it returns F<o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Thanks for any highlight<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Paul<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">##############################################################################”<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:#32B9B9">mode</span><span style="font-family:"Monospaced","serif";color:#4A55DB">(</span><span style="font-family:"Monospaced","serif";color:rosybrown">0</span><span style="font-family:"Monospaced","serif";color:#4A55DB">)</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif""> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><em><span style="font-family:"Monospaced","serif";color:#64AE64">// test 1</span></em><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:black">M</span><span style="font-family:"Monospaced","serif"">
<span style="color:#5C5C5C">=</span> <span style="color:#4A55DB">[]</span><span style="color:black">;</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:#A020F0">if</span><span style="font-family:"Monospaced","serif"">
<span style="color:black">M</span> <span style="color:#A020F0">then</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif"">
<span style="color:#32B9B9">printf</span><span style="color:#4A55DB">(</span><span style="color:rosybrown">"M returns T\n"</span><span style="color:#4A55DB">)</span><span style="color:black">;</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:#A020F0">else</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif"">
<span style="color:#32B9B9">printf</span><span style="color:#4A55DB">(</span><span style="color:rosybrown">"M returns F\n"</span><span style="color:#4A55DB">)</span><span style="color:black">;</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:#A020F0">end</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif""> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><em><span style="font-family:"Monospaced","serif";color:#64AE64">// test 2</span></em><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:black">a</span><span style="font-family:"Monospaced","serif";color:#5C5C5C">=</span><span style="font-family:"Monospaced","serif";color:#4A55DB">[]</span><span style="font-family:"Monospaced","serif";color:black">;</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:black">b</span><span style="font-family:"Monospaced","serif";color:#5C5C5C">=</span><span style="font-family:"Monospaced","serif";color:rosybrown">30</span><span style="font-family:"Monospaced","serif";color:black">;</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:black">c</span><span style="font-family:"Monospaced","serif";color:#5C5C5C">=</span><span style="font-family:"Monospaced","serif";color:rosybrown">200</span><span style="font-family:"Monospaced","serif";color:black">;</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif""> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:#A020F0">if</span><span style="font-family:"Monospaced","serif"">
<span style="color:#4A55DB">(</span><span style="color:black">b</span> <span style="color:#5C5C5C">
&</span> <span style="color:black">c</span> <span style="color:#5C5C5C">&</span> <span style="color:black">
a</span><span style="color:#4A55DB">)</span> <span style="color:#A020F0">then</span>
</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif""> <span style="color:#32B9B9">printf</span><span style="color:#4A55DB">(</span><span style="color:rosybrown">"val = 6\n"</span><span style="color:#4A55DB">)</span><span style="color:black">;</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif"">
<span style="color:#A020F0">else</span> <span style="color:#32B9B9">printf</span><span style="color:#4A55DB">(</span><span style="color:rosybrown">"val = []\n"</span><span style="color:#4A55DB">)</span><span style="color:black">;</span>
<em><span style="font-family:"Monospaced","serif";color:#64AE64">// should return [] ??????</span></em></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:#A020F0">end</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif""> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><em><span style="font-family:"Monospaced","serif";color:#64AE64">// test 3</span></em><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:black">tmp</span><span style="font-family:"Monospaced","serif"">
<span style="color:#5C5C5C">=</span> <span style="color:orchid">%f</span><span style="color:black">;</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><em><span style="font-family:"Monospaced","serif";color:#64AE64">//tmp = %t;</span></em><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif""> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:#A020F0">if</span><span style="font-family:"Monospaced","serif"">
<span style="color:#4A55DB">(</span><span style="color:black">tmp</span><span style="color:#4A55DB">)</span>
<span style="color:#A020F0">then</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif"">
<span style="color:#32B9B9">printf</span><span style="color:#4A55DB">(</span><span style="color:rosybrown">"tmp returns T\n"</span><span style="color:#4A55DB">)</span><span style="color:black">;</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:#A020F0">else</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif"">
<span style="color:#32B9B9">printf</span><span style="color:#4A55DB">(</span><span style="color:rosybrown">"tmp returns F\n"</span><span style="color:#4A55DB">)</span><span style="color:black">;</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:#A020F0">end</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif""> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><em><span style="font-family:"Monospaced","serif";color:#64AE64">// test 4</span></em><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:black">t1</span><span style="font-family:"Monospaced","serif"">
<span style="color:#5C5C5C">=</span> <span style="color:orchid">%t</span><span style="color:black">;</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:black">t2</span><span style="font-family:"Monospaced","serif"">
<span style="color:#5C5C5C">=</span> <span style="color:orchid">%t</span><span style="color:black">;</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><em><span style="font-family:"Monospaced","serif";color:#64AE64">//t3 = %t;</span></em><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:black">t3</span><span style="font-family:"Monospaced","serif"">
<span style="color:#5C5C5C">=</span> <span style="color:orchid">%f</span><span style="color:black">;</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif""> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:#A020F0">if</span><span style="font-family:"Monospaced","serif"">
<span style="color:#4A55DB">(</span><span style="color:black">t1</span> <span style="color:#5C5C5C">
&</span> <span style="color:black">t2</span> <span style="color:#5C5C5C">&</span>
<span style="color:black">t3</span><span style="color:#4A55DB">)</span> <span style="color:#A020F0">
then</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif"">
<span style="color:#32B9B9">printf</span><span style="color:#4A55DB">(</span><span style="color:rosybrown">"(t1,t2,t3) returns T\n"</span><span style="color:#4A55DB">)</span><span style="color:black">;</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:#A020F0">else</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif"">
<span style="color:#32B9B9">printf</span><span style="color:#4A55DB">(</span><span style="color:rosybrown">"(t1,t2,t3) returns F\n"</span><span style="color:#4A55DB">)</span><span style="color:black">;</span></span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Monospaced","serif";color:#A020F0">end</span><o:p></o:p></p>
<p><em><b><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:gray">EXPORT CONTROL :
</span></b></em><b><i><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:gray"><br>
</span></i></b><strong><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">Cet email ne contient pas de données techniques</span></strong><b><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black"><br>
<strong><span style="font-family:"Arial","sans-serif"">This email does not contain technical data</span></strong></span></b><span style="font-size:10.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<p class="MsoNormal"><span style="font-size:10.0pt"><o:p> </o:p></span></p>
<div>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">_______________________________________________<br>
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