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<p class="MsoNormal"><span lang="EN-US">Dear all,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I was using a code I developed in version 4.4 for meshing spheres with tetrahedron. I could modify the characteristic length (max. and min.) and it worked perfectly.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Moreover, I’ve been using this code in different incremental updates and it worked perfectly until version 4.5.3. Yesterday, I updated to version 4.5.6 and the code continues working but with a strange behavior.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Let’s say that I was using a characteristic length of 0.2 for meshing a sphere, in version 4.5.3 this resulted in ~70k elements. Now, with the same characteristics, this results in 1.000.000 elements!
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">No matter what I tried, it seems that GMSH’s response was invariant:<o:p></o:p></span></p>
<ul style="margin-top:0cm" type="disc">
<li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><span lang="EN-US">Activate/deactivate the optimization of the mesh (it did not change anything)<o:p></o:p></span></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><span lang="EN-US">Modify the characteristic length up to 2 or 4 (it did not change anything). Also, I debugged to be sure that these were the actual values that GMSH received<o:p></o:p></span></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><span lang="EN-US">Try to use a bias in the mesh. Nothing<o:p></o:p></span></li></ul>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Perhaps, I missed a major modification in the code from 4.5.3 to 4.5.6 and I need to re-code my libraries… but… Could it be a bug in the code? If so, where? In the meantime, I downgraded to version 4.5.3.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Tested in:<o:p></o:p></span></p>
<ul style="margin-top:0cm" type="disc">
<li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><span lang="EN-US">W10<o:p></o:p></span></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><span lang="EN-US">Ubuntu 18.04 in WSL (W10)<o:p></o:p></span></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><span lang="EN-US">Ubuntu 18.04<o:p></o:p></span></li></ul>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Best,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">MA<o:p></o:p></span></p>
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