The format would be 0.5+0.5j.
Hail,
I'm surprised that I haven't encountered this before but I am unable
to enter a complex number in a GRC field for example the "Signal Source"
block (gr version: 3.9.3). There doesn't appear to be documentation, at
least in an obvious place.
Entering (0.5,0.5) in the complex offset field yields:
Param - Offset(offset):
_expression_ (0.5, 0.5) is invalid for type 'complex'.
A single float value offsets I but not Q.
I apologize if I have missed something totally obvious.
BTW: the documentation is improving nicely over time; my compliments to
the contributors.
Rick