Validation test for the block Buildings.Controls.OBC.CDL.Routing.RealExtractor.
The instances extIndSig, extIndSig1, extIndSig2,
extIndSig3, and extIndSig4 have the same input vector with
dimension of 5. However, they have different extract index and thus different output.
extIndSig has the extract index of 2. The output is u[2].
extIndSig1 has the extract index of 6.
Thus it is out of upper range [1, 5] and it outputs u[5].
It also issues a warning to indicate that the extract index is out of range.
extIndSig2 has the extract index of 0.
Thus it is out of lower range [1, 5] and it outputs u[1].
It also issues a warning to indicate that the extract index is out of range.
extIndSig3 has the extract index changing from 2
to -1. Thus it first outputs u[2], and then changes to u[1].
At the moment when the extract index becomes out of range, it issues a warning.
extIndSig4 has the extract index changing from 0
to 3. Thus it first outputs u[1], and then changes to u[3].
It issues a warning at the start of the simulation.