There are three unwrapping algorithms available under
CALIBRATEVISIBILITYTRIPLE. For the first two, REWRAPTRIPLE
and DEWRAPTRIPLE, you have to have
calibrator stars selected first, since they unwrap only the data for
these stars (for the time being). Rewrapping here shall mean the
rotation of the complex visibility by a specified angle so that
the entire range of phases fits into the interval
degrees. The the phases are recomputed, and backrotation is applied
to the complex quantities, but merely subtracted from the phases.
If the phase is wrapping more rapidly, one should plot the
(calibrated) triple phase, and fit a low order polynomial to
a stretch which does not wrap (use FIT).
The fit parameters are passed to the unwrapping
algorithm, which removes it from the data and then removes
also the resulting steps. The fit is then reapplied to the data.
The manual unwrapping utility, MANUALUNWRAP,
will allow the user to place a box
into a plot of phase vs time or channel, and the data inside
will be rotated
or
degrees, as specified. No
calibrator stars need be specified for this operation.
Note that in this case the calibrated phase has to be plotted,
since this is the phase which is unwrapped!