Author Topic: Is occupancy modifier in expression selection is change in new version?  (Read 253 times)

prash

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Hello all,
I'm doing analysis of interstitial defects in my binary alloy. I was doing WignerSeitz analysis, followed with Expression selection to see Interstitial trajectory.
 
But I seen in Expression selection Occupancy >1 is not allowed now.
It shows option of Occupancy.1 and Occupancy.2.
I didn't understand how to deal with this. I tried to do something like this

Occupancy.1>1, Occupancy.2>1

But it does not work well.
Any help is appreciated.

Thank you

Constanze Kalcher

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Re: Is occupancy modifier in expression selection is change in new version?
« Reply #1 on: January 15, 2019, 11:15:59 AM »
Hello prash,

if you activate the option "compute per-type occupancies", the occupancy count is split into type-specific counts, see section Systems with more than one atomic species in the documentation:
http://www.ovito.org/manual_testing/particles.modifiers.wigner_seitz_analysis.html

Note that the Expression selection expects boolean expressions, which can be combined using logical AND and OR operators (&& and ||). So if you want to select sites, with more than one atom of type 1 and more than one atom of type 2, the expression would be Occupancy.1>1 && Occupancy.2>1. Moreover, to select sites that have a total occupancy larger than 1, you could use (Occupancy.1 + Occupancy.2) >1.

-Constanze
« Last Edit: January 15, 2019, 11:21:45 AM by Constanze Kalcher »