IBBM 2017

Loadcurve id and order
issueid=706 04-07-2015 09:57 AM
Junior Member
Loadcurve id and order

Hi,

It seems that in the LoadData section, the id of each load curve isn't taken into account by FEBio2 and that FEBio2 only counts the rank of each load curve (1 for the first from the top).

For instance this code:
Code:
<LoadData>
 		<loadcurve id="2" type="step">
 			<loadpoint>0,0</loadpoint>
 			<loadpoint>28.328,5</loadpoint>
 			<loadpoint>56.656,5</loadpoint>
 			<loadpoint>1000,50</loadpoint>
 			<loadpoint>10000,500</loadpoint>
 		</loadcurve>
 		<loadcurve id="1" type="step">
			<loadpoint>0,0</loadpoint>
			<loadpoint>1,-0.7308</loadpoint>
 		</loadcurve>
 	</LoadData>
Will be read by FEBio2 as lc="1" for the first loadcurve from the top (id="2") and as lc="2" for the last loadcurve from the top (id="1").

Regards,

Antoine.
Issue Details
Issue Number 706
Project FEBio
Category Unknown
Status Confirmed
Priority 4
Affected Version Unknown
Fixed Version (none)
Users able to reproduce bug 0
Users unable to reproduce bug 0
Assigned Users (none)
Tags (none)




07-13-2015 10:03 AM
Lead Code Developer
Hi Antoine,

This is true. Currently, the id attribute is ignored by FEBio and the internal id's of the load curves are simply determined by the order in which they are defined.

This is in fact the case for all tags that define an id attribute. FEBio ignores these attributes and uses an internal numbering based on order. Of course, for tags that can be referenced by other tags via their id (such as load curves) this can create confusion if the id's are not in numerical order.

To be honest, the id's are defined more for convenience to the users to make it easier to find certain tags in the file. Since things are easier to find if they are in ordered in some way, I'm not a big fan of allowing users to define the id's in random order. So, what I think I will do is throw an error message when someone defines a load curve out of order. Will that work for you or is there a compelling reason for defining load curves out of order?

Best,

Steve

07-13-2015 03:18 PM
Junior Member
Hi Steve,

You're right, there's no reason for defining load curves out of order. It's just that once I wanted to test something and inverse two load curves and instead of changing lc="LCID" I changed id="" in the LoadData section. I was surprised to see no change. I guess you just need to add a note in the User Manual. (And error message when LoadData or Materials are out of order would be a good idea too).

Best,

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