Ptycho: add range constraint to the object amplitude and phase
It would be useful to be able to constrain the object in some cases, with a range for the amplitude or phase.
This could be done using:
- an option (or algorithm step)
obj_amplitude_range=0,1
- another option
obj_phase_range=0,1.0
(between -pi and pi) - a special case could be using a negative lower bound for the amplitude, in which case the phase range should be within [-pi/2;pi/2], and with the possibility of using
obj_phase_range=0,0
to produce a real object (but possibly <0)
In practice this could be stored as an object constraint inside the Ptycho
object, rather than passed as a parameter to the multiple operators, which is cumbersome.