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<div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;">the start_id attribute refers to the unique file id (or we call it sometimes unique entity id) for each entity in an h5m format<br>
There is no relation with the GLOBAL_ID tag.<br>
file id is a moab convention<br>
GLOBAL_ID corresponds slightly to global id for a cubit file<br>
(so when you convert a cubit file, entities usually have global ids)<br>
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for moab, global ids are tags for entities, and usually global ids for vertices start from 1<br>
global ids for hexas start from 1 too. They are just attributes/tags associated to the data, they can be set, reset, without modifying the mesh. (at your own risk:)<br>
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file ids are unique identificators strictly related to moab hdf5 format<br>
When sets are specified in h5m format, they are specified in terms of file ids (as they are unique, there is no confusion)<br>
Also, connectivities are also specified using file ids (and not global ids for vertices, for example)<br>
<br>
<a href="http://ftp.mcs.anl.gov/pub/fathom/moab-docs/h5mmain.html" target="_blank">http://ftp.mcs.anl.gov/pub/fathom/moab-docs/h5mmain.html</a><br>
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<div style="direction: ltr;" id="divRpF67286"><font face="Tahoma" color="#000000" size="2"><b>From:</b> moab-dev-bounces@mcs.anl.gov [moab-dev-bounces@mcs.anl.gov] on behalf of Nico Schlömer [nico.schloemer@gmail.com]<br>
<b>Sent:</b> Monday, November 09, 2015 4:34 AM<br>
<b>To:</b> moab-dev@mcs.anl.gov<br>
<b>Subject:</b> [MOAB-dev] h5m: GLOBAL_ID<br>
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<div dir="ltr">Hi everyone,
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<div>I understand that in h5m, every entity is associated with a GLOBAL_ID. This ID is specified in the GLOBAL_ID array of the tags groups associated with, e.g., nodes or elements.</div>
<div><br>
</div>
<div>Now, I see that that in the example [1], the GLOBAL_ID array for nodes is</div>
<div>```</div>
<div>1 2 3 ... 409</div>
<div>```</div>
<div>and for elements it's</div>
<div>```</div>
<div>0 ... 758</div>
<div>```</div>
<div>To resolve the conflicts, the connectivity dataset of elements as the attribute `start_id = 410`, so I can just add that value to the above IDs and have them globally unique.</div>
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<div>What's confusing me is that coordinates dataset of nodes also has an attribute `start_id` and it's value is `1`! So, no adding to GLOBAL_ID array in this case, for some reason?</div>
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<div>Cheers,</div>
<div>Nico</div>
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<div>[1] <a href="http://chunk.io/f/d24c8c0a3ebc413bbd7c40209767a21c" target="_blank">http://chunk.io/f/d24c8c0a3ebc413bbd7c40209767a21c</a></div>
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