My launch simulation's producing numbers on the order of 1e-12 and sometimes smaller.
I can't imagine that any sensor would be so precise and therefore that 10+ decimal places would be meaningful or appropriate.
And even if sensor readings were that precise, I can't imagine it being good use of memory to store numbers to the 10th+ decimal place.
This has me wondering (and please excuse the dumb question, as I am not a computer scientist): how precise do GNC numbers get? How many decimal places would position/velocity state vectors retain? Would they be stored with more decimal places than the precision of their sources (sensors) justifies?
(E.g., if position measurements were precise to within 0.1 m, then would position vectors be stored with more than one decimal place when expressed in m?)
guard bits
. Because, it helps to retain the additional bits generated on intermediate results. The truncation, if any, is better done on the final result and not on the intermediate results. $\endgroup$