Stray extra 'q' in subscripts of figure 15.1

[henrikt-ma]

In figure 15.1 at the beginning of section 15.2 Stream Operator inStream and Connection Equations, the labels on the outside connector symbols have a 'q' in the subscripts before the index. I can't see what that letter corresponds to in the text; should it be there at all?

[HansOlsson]

I cannot see that the "q," should be there either. It was introduced in version 3.1 and I cannot see any explanation for it any underlying document. (Powerpoint etc.)

[henrikt-ma]

OK, then I'll remove it together with the other work on figures in #2609.