[Chimera-users] Geometric objects

[Elaine Meng]

Hi Reza,
Well, the one you get from "measure inertia" is meant to show the dimensions of the the principal axes, so you couldn't get a smaller one from that command unless you used different/fewer atoms.  There is no command to shrink it after you make it.
<https://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/measure.html#inertia>

 However, you can draw an ellipsoid surface of whatever size you want with "shape ellipsoid", see command options:
<https://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/shape.html#ellipsoid>

Each of the commands above is mentioned in the "see also" of the other, since they are the ways to draw an ellipsoid.  Geometric objects can also be defined in BILD format and a few other ways, but they do not include ellipsoids. 
<https://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/print.html#objects>

I hope this helps,
Elaine
-----
Elaine C. Meng, Ph.D.                       
UCSF Chimera(X) team
Department of Pharmaceutical Chemistry
University of California, San Francisco

> On Aug 17, 2022, at 2:07 PM, Reza Khayat via Chimera-users <chimera-users at cgl.ucsf.edu> wrote:
> 
> Hi,
> Can the size of geometric objects be changed? For example, can I make the ellipsoid drawn by command "measure inertia #0:167-285.A" smaller? Thanks.
> Best wishes,
> Reza