<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: times new roman,new york,times,serif; font-size: 12pt; color: #000000'><br><br><hr id="zwchr"><blockquote id="DWT243" style="border-left:2px solid #1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;"><br>On 13 Jul 2013, at 23:52, Iulian Grindeanu <iulian@mcs.anl.gov> wrote:<br><br>> Hello Lukasz,<br>> <br>> Hello,<br>> <br>> I storing entity handle on tags. I use that to store handle to parent element in edge mesh refine algorithm. To create tag I use,<br>> <br>> //CASE 1<br>> rval = moab.tag_get_handle("_RefParentHandle",sizeof(EntityHandle),<br>> MB_TYPE_OPAQUE,th_RefParentHandle,MB_TAG_CREAT|MB_TAG_SPARSE|MB_TAG_BYTES,&no_handle); CHKERR(rval); CHKERR_THROW(rval);<br>> <br>> or<br>> <br>> //CASE 2<br>> rval = moab.tag_get_handle("_RefParentHandle",1,<br>> MB_TYPE_HANDLE,th_RefParentHandle,MB_TAG_CREAT|MB_TAG_SPARSE,&no_handle); CHKERR(rval); CHKERR_THROW(rval);<br>> <br>> I think the issue is "no_handle" definition in your code. EntityHandle is basically unsigned long int. (-1) will be probably converted to 0xfff...fff, but I think it depends on compiler.<br>> for type MB_ENTITY_HANDLE, during writing, it will try to map with an actual handle, and it will not be able to.<br>> It should probably give some warning at least. <br>It was my intention to have impossible tag. However in that case root_mesh is also impossible, to be parent and will do work. <br><br>It is funny, that no_hanle(-1) working without warning, problems is when I read file. In other words I can create tag and use it without problems. However when I restart calculations and read file I have error. <br><br></blockquote>well, we use ~(EntityHandle)0 in our tests, and it would be the same problem during saving to an h5m file.<br><blockquote id="DWT244" style="border-left:2px solid #1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;">> It is not advisable to use OPAQUE type, because it will just set the handle in bytes. If some reordering is involved, you could get a different handle than you expect.<br>> Would it be difficult to use 0 as default in your code? (root set?) Nobody should have as "parent" the root set, but I am not understanding your code enough; <br>> Or create an actual entity (or an entity set) that you know that you will never use, and use that for default. I assume that you need a default, but maybe you don't. <br>I was not aware of that tags which has type ENTITYHANDLE are automatically updated in case of reordering. I was thinking that Handle is given to Entity for its life in database and no other, dead or alive entity can share the same handle.<br><br></blockquote>Yes, entity handle is unique per moab instance. But the tag of type MB_TYPE_HANDLE can point to any entity handle; <br>Of course, if you delete that entity handle, all bets are off, we do not keep track. It would be like a pointer to deleted memory.<br><blockquote style="border-left:2px solid #1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;"></blockquote><br>The entities are mapped to hdf5 file entity ids during writing, and during reading they are mapped back to moab entity handles.<br><br>If you want to know more about h5m format, you can find here some info<br>http://trac.mcs.anl.gov/projects/ITAPS/wiki/MOAB/h5m<br><br><blockquote id="DWT245" style="border-left:2px solid #1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;">Ok mesh merging is a problem. <br><br></blockquote>yes, it would be; if you use handle tag, you would have no problems. Please report if you find any bugs.<br><blockquote id="DWT247" style="border-left:2px solid #1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;">> I looked a little at your h5m files, there are a lot of tags, nice and elaborate work :) I hope you keep track of them :)<br>I hope as well, tags content is controlled by boost multi-index containers.<br></blockquote>I would like to be able to compile your code; it seems you depend on PETSc; any other dependencies?<br>We want to add more support for mesh refinement, and your experience would help us.<br><br>Thanks,<br>Iulian<br><blockquote style="border-left:2px solid #1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;"><br>> I did not compile your code, are there any instructions? I see that for cmake you need some file to be defined. (for PETSc?)<br><br>Yes, mesh is serial, calculations are parallel and I use PETSc to do that.<br><br>> Best regards,<br>> Iulian<br>> <br>> I save mesh in native moab format and read it once again. <br>> <br>> In CASE 1, moab works as expected, no problem. See example file restart_case1.h5m. <br>> In CASE 2, moab generate error,<br>> Error code 10 at /Users/likask/MyBuild/mofem-bitbucket/mofem_v0.0.1/do_not_blink/moabField_Core.cpp:46<br>> See example file restart_case2.h5m<br>> <br>> I don't know if error is result of my ignorance about moab, or problem is somewhere in moab implementation. I using version moab-4.6.0. <br>> <br>> <br>> If you need more details about my code, you can find code here, <br>> https://bitbucket.org/likask/mofem-joseph/overview<br>> Tag: <br>> v0.0.1.1_moab_problem_with_tag<br>> <br>> Thanks for help,<br>> Regards,<br>> Lukasz Kaczmarczyk<br>> Lecturer<br>> School of Engineering,<br>> University of Glasgow,<br>> GLASGOW, G12 8LT<br>> Tel: +44 141 3308113<br>> email: likask@civil.gla.ac.uk<br>> web: http://userweb.eng.gla.ac.uk/lukasz.kaczmarczyk<br><br></blockquote><br></div></body></html>