API Question PMI problem: getting three vectors into one

astrosammy

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This is what I did wrong, three vectors, but only one is allowed:
Code:
[SIZE=2]
SetPMI (_V(3.1,0,0), _V(0,3.42,-0.4), _V(0,-0.4,0.68));
[/SIZE]

How do I get the three vectors (from shipedit.exe) into the correct format for the SetPMI function? Is it just a simple calculation, like addition of the vectors?
 

Urwumpe

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Orbiter only uses the diagonal of the tensor - the off diagonal components are actually CoG offset.
 

mjessick

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The Principal Moments of Inertia (initials PMI) are the diagonal components of the 3 by 3 matrix. (The other 6 elements are called products of inertia. To simplify calculations, they can sometimes be neglected.)

So you want:
SetPMI (_V(3.1, 3.42, 0.68));
 
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