Hi Judy, can you clarify where you see those values being used in the the Aerospace Blockset?
Those values are close to the initial conditions of the CubeSat Simulation Library "CubeSat Simulation Project" template, but are missing significant digits. The actual values used are [-5762639.8158 -1682742.0789 3156028.3952] :
sqrt(sum([-5762639.8158 -1682742.0789 3156028.3952].^2)) = 6.782341320079139e+06
while Earth's equatorial radius is ~6378.137km (https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html)
6782341 - 6378137 = 404204
This ~404km altitude corresponds with the average altitude of the International Space Station, which was the reference orbit for this example.
Hope that helps,
Collin