Basic Information on uvamp

Task: uvamp
Purpose: Annular averages a uv dataset in bins. Prints and plots results.
Categories: uv analysis

        UVAMP reads a uv dataset, bins the data in annuli according to
        uv distance and prints/plots vector averaged amplitude versus
        uvdist. Statistical error bars and the expected amplitude for
        zero signal are calculated.

Key: vis
        The name of the input uv data set. No default.

Key: select
        The normal uv selection commands.

Key: line
        The normal uv linetype in the form:
          line,nchan,start,width,step
        The default is all channels (or all wide channels if there are no
        spectral channels). The output will consist of only spectral or
        wideband data (but not both). If spectral averaging is performed
        (``width'' not equal to 1), then the output will be written as a
        single spectral window.

Key: ref
        The normal reference linetype, in the form:
          line,start,width
        The default is no reference line.

Key: stokes
        If a value is given, uvamp will work with the specified
        polarizations. Normally this should be set to stokes I if
        the data includes polarizations.

Key: options
        This gives extra processing options. Several options can be given,
        each separated by commas. They may be abbreviated to the minimum
        needed to avoid ambiguity. Possible options are:
           'nocal'       Do not apply the gains file. By default, UVAMP
                         applies the gains file in copying the data.
           'nopol'       Do not apply polarizatiopn corrections. By default
                         UVAMP corrects for polarization cross-talk.
           'nopass'      DO not apply bandpass corrections. By default
                         UVAMP corrects for the bandpass shape.
           'ampscalar'   Applies vector averaging to work out the
                         averaged visibility phase, but scalar averaging
                         to find the averaged visibility amplitude.

Key: bin
        Number of bins, width of bins, and units of bin width. Up to 200
        bins are allowed. The units for bin width may be either nsec or
        klam. The default unit for bin width is nsecs.
        Default values: 30,40,nsec

Key: offset
        RA-Dec offset of desired phase center relative to phase center
        of original uv dataset in arcseconds. Source of interest should be
        at the phase center in the typical use of this program.
        Default = 0.0,0.0.

Key: type
        Calculate the amplitude and standard deviation for each bin based on
        the real and imaginary components (total) or just based on the real
        component (real). The "real" option is useful if your expected source
        visibility is entirely real -- i.e. a point source or circularly
        symmetric source at the phase center.
        Possible options are "total" and "real". Default: total.

Key: device
        Plot device name. If not specified, no plot is created.

Key: log
        Log file name. Default is no log file.