General Question Define Position/Velocity Pair?

[Interstellar Planet]

I just ran into something in OrbiterConfig.pdf that I never heard of before.

In the planet configuration section (2.3) it says the following about the "HasElements" bool:

If TRUE, the initial position/velocity is calculated from the provided set of orbital elements, otherwise from an explicit position/velocity pair (ignored if module supports position/velocity calculation)

Does anyone know how to define a position/velocity pair for a planet? It never describes how to do so in the manual.