# IsSampleEvalMode

IsSampleEvalMode is a system variable that returns True (1) when evaluated in Prob (probabilistic) mode or False (0) when evaluated in Mid (deterministic) mode. For example:

Mid(IsSampleEvalMode) → 0
Sample(IsSampleEvalMode) → 1

It is useful when you write an expression, e.g. a function, that uses different logic in each case -- for example:

If IsSampleEvalMode then <<logic to generate a sample>>
Else <<logic to compute the median>>