<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On 4 Mar 2018, at 18:46, Juan E. Sanchez <<a href="mailto:juan.e.sanchez@gmail.com" class="">juan.e.sanchez@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="">Hi Christophe,<br class=""><br class="">In my actual structure, it is unknown whether or not it will be split. There will also be many more volumes with different tags.<br class=""><br class="">I also do not want "air" to contain any of "gate".<br class=""><br class="">How do I get all volumes created from the BooleanDifference into the same Physical Volume?<br class=""><br class=""></div></div></blockquote><div><br class=""></div><div>Use the list (note the "()") returned by the boolean command :</div><div><br class=""></div><div><div>air()=BooleanDifference{Volume{air}; Delete;}{ Volume{gate};};</div><div><br class=""></div><div>Recursive Delete{Volume{unit_box};}</div><div>BooleanFragments{ Volume{air()}; Volume{gate}; Delete;}{}</div><div><br class=""></div><div>Physical Volume ("gate") = {gate};</div><div>Physical Volume ("air") = {air()};</div><div class=""><br class=""></div></div><div><br class=""></div><br class=""><blockquote type="cite" class=""><div class=""><div class="">Regards,<br class=""><br class="">Juan<br class=""><br class=""><br class=""><br class="">On 3/4/18 11:29 AM, Christophe Geuzaine wrote:<br class=""><blockquote type="cite" class=""><blockquote type="cite" class="">On 4 Mar 2018, at 17:46, Juan E. Sanchez <<a href="mailto:juan.e.sanchez@gmail.com" class="">juan.e.sanchez@gmail.com</a> <<a href="mailto:juan.e.sanchez@gmail.com" class="">mailto:juan.e.sanchez@gmail.com</a>>> wrote:<br class=""><br class="">Using the latest Mac OS snapshot, it is the same behavior.<br class=""><br class="">3 sections appear (air, gate, air)<br class=""><br class="">I go into the visibility dialog, visualize both "gate" and "air", and the last "air" disappears.<br class=""><br class=""></blockquote>I think you are misunderstanding the definition of physical groups. Your boolean operations create 3 elementary volumes : left, center and right. You put the left one in the physical group "air" and the middle one in "gate". (Note that your boolean operations are unnecessarily complicated - you could just fragment the 2 boxes instead of doing a difference followed by a fragment.)<br class="">So if you select the 2 physical groups, indeed you hide the right volume...<br class=""><blockquote type="cite" class="">If I mesh before opening the visibility dialog, all 3 sections get meshed.<br class=""><br class=""></blockquote>Normal again: by default with the MSH2 format Gmsh only saves elements that belong to physical groupe.<br class=""><blockquote type="cite" class="">When I save the mesh, and then open the mesh file, one of the "air" sections is missing.<br class=""><br class=""><br class="">Starting over:<br class=""><br class="">If I open the visibility dialog, and select both physical groups, one of the "air" sections disappear.<br class=""><br class="">Looking in the Elementary entities, it appears that there are 3 volumes. It looks like one of the "air" sections did not get assigned to the Physical Group.<br class=""><br class="">How do I ensure that both "air" sections get assigned to the same Physical Group?<br class=""><br class=""></blockquote>Physical Group ("air") = {3,4};<br class="">Christophe<br class=""><blockquote type="cite" class="">Regards,<br class=""><br class="">Juan<br class=""><br class=""><br class=""><br class=""><br class="">On 3/4/18 1:21 AM, Christophe Geuzaine wrote:<br class=""><blockquote type="cite" class="">Dear Juan,<br class="">Not sure what you observe - your file seems to behave normally with the latest version. Can you try with the latest automated snapshot ?<br class="">Christophe<br class=""><blockquote type="cite" class="">On 3 Mar 2018, at 20:40, Juan E. Sanchez <<a href="mailto:juan.e.sanchez@gmail.com" class="">juan.e.sanchez@gmail.com</a> <<a href="mailto:juan.e.sanchez@gmail.com" class="">mailto:juan.e.sanchez@gmail.com</a>> <<a href="mailto:juan.e.sanchez@gmail.com" class="">mailto:juan.e.sanchez@gmail.com</a>>> wrote:<br class=""><br class="">Hello,<br class=""><br class="">I am using the OpenCASCADE factory to create a fairly complicated structure. In this simplified test case, I run into the issue where part of the structure disappears when the center of it is removed.<br class=""><br class="">When GMSH opens the file, it looks correct. Then when I start manipulating it in the Visibility dialog, half of the "air" volume disappears.<br class=""><br class="">When 3d meshing half of the "air" volume is also missing.<br class=""><br class="">When I reopen the saved mesh, half the "air" volume is also missing.<br class=""><br class="">Could someone please take a look?<br class=""><br class=""><br class="">Regards,<br class=""><br class="">Juan Sanchez<br class=""><test.geo>_______________________________________________<br class="">gmsh mailing list<br class=""><a href="mailto:gmsh@onelab.info" class="">gmsh@onelab.info</a> <<a href="mailto:gmsh@onelab.info" class="">mailto:gmsh@onelab.info</a>> <<a href="mailto:gmsh@onelab.info" class="">mailto:gmsh@onelab.info</a>><br class=""><a href="http://onelab.info/mailman/listinfo/gmsh" class="">http://onelab.info/mailman/listinfo/gmsh</a><br class=""></blockquote>—<br class="">Prof. Christophe Geuzaine<br class="">University of Liege, Electrical Engineering and Computer Science<br class=""><a href="http://www.montefiore.ulg.ac.be/~geuzaine" class="">http://www.montefiore.ulg.ac.be/~geuzaine</a><br class="">Free software: http://gmsh.info | http://getdp.info | http://onelab.info<br class=""></blockquote><br class=""></blockquote>—<br class="">Prof. Christophe Geuzaine<br class="">University of Liege, Electrical Engineering and Computer Science<br class=""><a href="http://www.montefiore.ulg.ac.be/~geuzaine" class="">http://www.montefiore.ulg.ac.be/~geuzaine</a><br class="">Free software: http://gmsh.info | http://getdp.info | http://onelab.info<br class=""></blockquote><br class=""></div></div></blockquote></div><br class=""><div class="">
<div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;">— </div><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;">Prof. Christophe Geuzaine<br class="">University of Liege, Electrical Engineering and Computer Science <br class=""><a href="http://www.montefiore.ulg.ac.be/~geuzaine" class="">http://www.montefiore.ulg.ac.be/~geuzaine</a><br class=""><br class="">Free software: http://gmsh.info | http://getdp.info | http://onelab.info</div></div>
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