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Basic Information on uvplt


Task: uvplt
Purpose: Make plots from a UV-data base on a PGPLOT device.
Categories: uv analysis, plotting

        UVPLT plots a variety of quantities from visibility data bases.
        Options are available to time average data (plot with optional
        error bars) and to plot different baselines on separate
        sub-plots on each page plus many others.
 

Key: vis
        The input visibility file(s). Multiple input files and wild card
        card expansion are supported.
        No default

Key: line
        This is the normal linetype specification. See the help on
        line for more information.  The default is all channels.

Key: select
        This selects which visibilities to be used. Default is all
        visibilities. See the Users Guide for information about how
        to specify uv data selection.
        Default is all data

Key: stokes
        Select Stokes parameter(s) or polarization(s) from:
          xx, yy, xy, yx,  i, q, u, v,
          rr, ll, rl, lr
        Default is all polarizations or Stokes parameters present

Key: axis
        Two values (minimum match active), one for each of the x
        and y axes chosen from:
          time                     [time in DD HH MM SS.S format]
          dtime                    [time in decimal days format]
          ytime                    [time in decimal years format]
          amplitude, real, imag    [natural units; Jy]
          phase                    [degrees]
          uu, vv                   [u & v in klambda]
          uc, vc                   [u,& v, -u & -v in klambda]
          uvdistance               [sqrt(u**2+v**2)]
          uvangle                  [uv pos'n angle clockwise from v
                                    axis]
          hangle                   [hour angle in HH MM SS.S]
          dhangle                  [hour angle in decimal hours]
          lst                      [local sidereal time in decimal hr]
          az                       [azimuth in degrees]
          el                       [elevation in degrees]
          airmass                  [airmass=1/sin(el)]
          jyperk                   [system gain, in Jy/K]
          rms                      [theoretical visibility noise rms, in
                                    flux units]
          freq                     [frequency, in GHz]
          parang                   [parallactic angle in degrees]
 
        NOTE: parang is the true parallactic angle of the source, which
        can be quite different from the angle between source and antenna
        feed (Miriad variable chi).
 
        Defaults are axis=time,amp  (x and y axes).

Key: xrange
        Plot range in the x-direction
          If axis = uu, vv, or uvdistance [kilo-lambda;   2 values]
                  unless OPTIONS=NANOSEC;     then   nanoseconds]
          If axis = uvangle               [degrees;       2 values]
          If axis = time                  [dd,hh,mm,ss.s; 8 values]
          If axis = dtime                 [decimal days;  2 values]
          If axis = amplitude, real, imag [natural units; 2 values]
          If axis = phase                 [degrees;       2 values]
          If axis = hangle                [hh,mm,ss.s;    6 values]
          If axis = dhangle               [decimal hours; 2 values]
          If axis = parang                [degrees;       2 values]
          If axis = az or el              [degrees;       2 values]
          If axis = airmass               [natural units; 2 values]
          If axis = jyperk                [Jy/K;          2 values]
          If axis = rms                   [flux units;    2 values]
          If axis = lst                   [decimal hours; 2 values]
          If axis = freq                  [GHz;           2 values]
 
        For axis types other than 'time' or 'hangle', one or other of
        the limits may be set with the other self-scaled by specifying
        the lower limit as 'min' and the upper as 'max' (or simply
        omitting it).  For example,
 
          xrange=min,0
 
        self-scales the lower limit while pinning the upper limit to
        zero, whereas either of the following
 
          xrange=0,max
          xrange=0
 
        set the lower limit to zero while self-scaling the upper limit.
 
        Default is to self-scale both limits (see also OPTIONS=XIND).

Key: yrange
        Plot range for the y-axis as for the x-axis.  The default is to
        self-scale (see also OPTIONS=YIND).

Key: average
        The averaging time in min (unless OPTIONS=DAYS,HOURS,SECONDS).
        Averaging is reset at frequency, source, or pointing centre
        changes.  Individual baselines and polarizations are averaged
        separately (unless OPTIONS=AVALL).  If you have selected
        multiple channels and you also ask for time averaging, then all
        the selected channels are averaged together in the time
        interval.  If you wish to use OPTIONS=AVALL to average
        everything on the one subplot (e.g. polarizations) but don't
        want temporal averaging, set AVERAGE to less than one
        integration.
        Default is no averaging.

Key: hann
        Hanning smoothing length (an odd integer < 15).   Is applied
        after any time averaging and INC selection. Useful for amplitude
        or phase, say, plotted against time.  Error bars remain
        unaffected by Hanning smoothing.  Currently, the Hanning
        smoothing is unaware of source or frequency changes.  Use SELECT
        if you have boundary problems.
        Default is no smoothing (hann = 1).

Key: inc
        Plot every INCth point (on each sub-plot) that would normally
        have been selected.   Useful if you don't want to average, but
        want to cut down on the number of plotted points.  Beware of
        increments that divide exactly into the number of baselines
        in time ordered data.
        Default is 1.

Key: options
        Task enrichment options. Minimum match is effective.
         nocal   Do not apply the gain corrections
         nopol   Do not apply the polarization leakage corrections
         nopass  Do not apply the bandpass corrections
 
         nofqav  By default, uvplt averages together all channels from
                 a visibility record before plotting. The nofqav option
                 disables this, and causes individual channels to be
                 plotted.  Note that this option is not active when time
                 averaging is invoked (frequency averaging is always
                 done then).
 
         nobase  Plot all baselines on the same plot, otherwise
                 each baseline is plotted on a separate sub-plot.
 
         notitle Do not write any title on the plot.  Probably most
                 useful if plotting all baselines on the same plot
                 (using the "nobase" option).
 
         2pass   Normally uvplt makes assumptions about what it is
                 expecting to find in the data regarding polarizations
                 and baselines.   Under some conditions, uvplt may
                 report that it has not allocated sufficient buffer
                 space.  This option instructs uvplt to make two passes
                 through the data, the first to accumulate precise
                 information on the contents of the selected data so
                 that buffer space is optimally allocated.
 
         scalar  Do scalar (average amplitudes or phases) rather than
                 vector (average real and imaginary) averaging.
                 This is useful if the visibilities are uncalibrated &
                 the phase is winding over the averaging interval & you
                 would like an averaged amplitude. Scalar averaged phase
                 is not very meaningful in general.
         avall   If you are averaging in time, then average all data
                 selected on each sub-plot together.  E.g. all selected
                 polarizations, and, if OPTIONS=NOBASE, all baselines
                 as well.  If you wish to average all the things on one
                 subplot together but without temporal averaging, just
                 set the averaging time to less than one integration.
         unwrap  When plotting phase, try to unwrap it so that
                 say, if one point is 179 deg and the next -179,
                 they will be plotted as 179 and 181 deg.  NOTE:
                 Unwrapping noise can be VERY misleading.
 
         rms     Draw error bars (+/- 1 standard deviation) on the plot
                 if averaging is invoked.
         mrms    Draw error bars (+/- 1 standard deviation in the mean)
                 on the plot if averaging is invoked.
         noerr   The automatically worked out min and max plot limits
                 will NOT include the ends of the error bars.
 
         all     Plot flagged and unflagged visibilties
         flagged Plot only flagged visibilities.  The default is to plot
                 only unflagged (good) visibilities.
                 ALL overrides FLAGGED.
 
         nanosec u and v are plotted in nano-seconds rather than
                 k-lambda
         days    The averaging interval is in days rather than minutes
         hours   The averaging interval is in hours rather than minutes
         seconds The averaging time is in seconds rather than minutes
 
         xind    If the x-axis is self-scaled, then unless
                 OPTIONS=NOBASE, setting XIND will cause each sub-plot
                 to have the x-axis self-scaled independently.  The
                 default is that the x-range used is that which
                 encompasses the ranges from all sub-plots.
         yind    The equivalent for the y-axis
 
         equal   Plot x and y with equal scales.  Useful only for plots
                 like AXIS=UU,VV.  Does not mean the plot will
                 necessarily be square
         zero    Plot the x=0 and y=0 lines
 
         symbols Each file is plotted with a different plot symbol
         nocolour
                 Each file is plotted with the same colour (white). By
                 default and when there is only one polarization, each
                 file has a separate colour.
         dots    If time averaging is invoked, plot the data with dots
                 rather than filled in circles.  These plot much faster
                 on hardcopy devices.
 
         source  Put the source name rather than the file name in the
                 plot title
         inter   After the plot is drawn, you get a chance to redraw
                 the plot with a different x- and y-range, and also
                 on a different device.  In this way you can make a
                 hard-copy without re-running the program. In this case,
                 points outside of the user specified x,y-range ARE
                 included in the plot buffer, so that if you redefine
                 the ranges, those points are available for plotting.
 
         log     Write the values and errors (if averaging) that are
                 plotted into the log file.  No attempt to separate
                 baselines is made, except that automatically obtained
                 by not setting OPTIONS=NOBASE

Key: subtitle
        Second line of title for plot (the first line is generated
        automatically).  Default is no sub-title.

Key: device
        PGPLOT plot device/type.  No default.

Key: nxy
        Number of plots in the x and y directions for when plotting
        each baseline separately. Defaults try to choose something
        sensible.

Key: size
        PGPLOT character sizes, in units of the default size (i.e., 1)
        First value is for the labels, the second is for the symbol size
        Defaults depend upon the number of sub-plots. The second value
        defaults to the first.

Key: log
        The output logfile name. The default is the terminal.

Key: comment
        A one line comment which is written into the logfile.
 
Revision: 1.18, 2014/05/21 04:34:59 UTC

Generated by miriad@atnf.csiro.au on 21 May 2014