yade-users team mailing list archive

[Bruno Chareyre <bruno.chareyre@xxxxxxxxxxx>]

Hello

Be aware that if you use the "normalize" function from wm3, it might 
give the result (0,0,0) if the norm of the vector is smaller than a 
"tolerance" value.
It sounds very strange to me, as I see no reason for this check, and I 
was wondering if it could not cause problems in some cases, when a 
"normalized" vector has length 0...
Janek had this problem when defining the normal of some triangular 
facets (of small size) by normalizing the cross product of edges vectors.
I prefer not to be the only one thinking about this potential problem, 
which probably needs a fix.

A few ideas from a discussion with Janek :
1- possibly fix minWm3 so that the test vs. tolerance is removed
2- display a warning to the user when the tolerance is hit and the 
vector is "rounded" to (0,0,0)
3-  run batch tests with/without the tolerance test

Bruno



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