Content-type: text/html Manpage of pgflag

pgflag

Section: User Commands (1)
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NAME

pgflag - Displays waterfall plots of uv data and allows flagging  

PERSON RESPONSIBLE

jbs  

CATEGORIES

flagging  

DESCRIPTION

PGFLAG is a MIRIAD task that allows interactive baseline editing of a UV data set. It is much like the MIRIAD task TVFLAG, but it uses the PGPLOT display devices instead of of the TV devices, which should make it more accessible.

When this program is run, the first selectable baseline is displayed as a greyscale waterfall plot. The x-axis is labelled as channel number (increasing to the right), while the y-axis represents time (later is toward the top of the plot). The colour intensity represents the amplitude or phase (depending on the value of the keyword ``mode'') of the visibility. At the very right and bottom edges of the plot are averages of the data over all the channels and times respectively. Between the right-hand average and the main plot is a colour wedge that shows the amplitude/phase scaling. At the top of the plot is a box with information about the baseline that is being viewed, the last taken measurement, and a guide to the commonly required action keys.

The user may edit the data by selecting a range of channels and times with the mouse, and then flagging or unflagging them. Selecting a range of channels and times is done by selecting two points - one with the left mouse button and one with the right mouse button - that bound the desired range. When a selection is made with either the left mouse button or the right mouse button, a green point will be placed on the screen at the selected location. If both a left mouse selection and a right mouse selection have been made, a green box will be displayed that will have the two selected points as opposite corners. Selecting another point with either the left mouse button or the right mouse button will move the appropriate corner of the box to form a new selection.

To act upon this selection, or the plot itself, the user should press one of the following keys while the cursor is inside the main plot area:

Exiting PGFLAG:

  a                Abort the editing procedure and quit
                   PGFLAG immediately without applying
                   any flags.
  q                Apply any flagging that was requested
                   and then exit PGFLAG.

Editing data:

  f                Flag the selected range of data on the
                   currently displayed baseline only.
  F                Flag the selected range of data on all
                   the selectable baselines.
  g                Unflag the selected range of data on the
                   currently displayed baseline only.
  G                Unflag the selected range of data on all
                   the selectable baselines.
  u                Undo the last flagging action - if the
                   last flagging action was an undo of a
                   previous flagging action, then the effect
                   will be to redo the flagging.
  1                Flag the selected range of data on all
                   baselines A-n formed with the currently
                   displayed antenna A.
  !                Unflag the selected range of data on all
                   baselines A-n formed with the currently
                   displayed antenna A.
  2                Flag the selected range of data on all
                   baselines n-B formed with the currently
                   displayed antenna B.
  @                Unflag the selected range of data on all
                   baselines n-B formed with the currently
                   displayed antenna B.
  v                Flag all visibilities that have values
                   greater than the current maximum on the
                   scale on the displayed baseline, for this
                   baseline only.
  V                Flag all visibilities that have values
                   greater than the current maximum on the
                   scale on the displayed baseline, for all
                   baselines.
  rr               Remove all current user-specified flags
                   on this baseline; r must be pressed twice
                   in a row for safety as this procedure
                   cannot be undone.
  RR               Remove all current user-specified flags
                   on all baselines; R must be pressed twice
                   in a row for safety as this procedure
                   cannot be undone.
  ?                Print some information about how many flagging
                   operations have been made so far in total
                   and on this baseline.

Manipulating the selection:

  c                Extend the selection box to include all
                   the displayed channels; press it twice in a row
                   to extend to all channels.
  t                Extend the selection box to include all
                   the displayed times; press it twice in a row to
                   extend to all times.
  C                Clear the selected points.

Manipulating the plot:

  z                Zoom into the selected region, ie. make
                   the selected region cover the entire plot,
                   and display green arrows on the sides of
                   the plot to indicate available scrolling
                   directions.
  Z                Unzoom to show all the available data.
  s                Unzoom to show all the available channels.
  S                Unzoom to show all the available times.
  h                Move the plot left by half the range shown
                   on the plot.
  H                Move the plot left by the range shown on the
                   plot.
  j                Move the plot down by half the range shown
                   on the plot.
  J                Move the plot down by the range shown on the
                   plot.
  k                Move the plot up by half the range shown
                   on the plot.
  K                Move the plot up by the range shown on the
                   plot.
  l                Move the plot right by half the range shown
                   on the plot.
  L                Move the plot right by the range shown on the
                   plot.
  n                Display the next selectable baseline in the
                   main plot, leaving the selection and zoom
                   as is.
  p                Display the previous selectable baseline in
                   the main plot, leaving the selection and
                   zoom as is.
  x                Subtract the average channel value from each
                   channel value in the main plot. Pressing this
                   key again adds back the average channel value
                   to each channel value. When the channel average
                   is being subtracted, the channel average box
                   at the bottom of the plot will be outlined in
                   red, otherwise it will be outlined in white.
  d                Subtract the average time value from each
                   time value in the main plot. Pressing this
                   key again adds back the average time value to
                   each time value. When the time average is being
                   subtracted, the time average box at the right
                   of the plot will be outlined in red, otherwise
                   it will be outlined in white.
  ,                Fiddle the amplitude scale; press this key
                   then click the left mouse button in the colour
                   wedge to set the maximum value, or the right
                   mouse button to set the minimum value.
  .                Reset the user-set colour amplitude scale.
  [                Enable switch to use only the currently
                   displayed points when deciding the colour
                   amplitude scale.
  ]                Set the colour amplitude scale from the current
                   selection region.
  ;                Lock the colour amplitude scale until it is
                   reset or fiddled.

Displaying information:

  m                Display information about the sample
                   underneath the cursor, including the channel
                   number (and associated frequency), the
                   time, and the amplitude (or phase depending
                   on the ``mode'' setting); all this information
                   is shown at the top left of the plot in the red
                   box.
  spacebar         Does the same thing as 'm', except it will show
                   the currently displayed value, which will be
                   different from the value displayed by 'm' if
                   the averages have been subtracted from the
                   display.
  M                Locate the sample with the maximum value on
                   the currently displayed baseline, and print
                   information about it into the controlling
                   terminal. Pressing it twice in succession will
                   make PGFLAG create a selection region of 20
                   chans and 20 times centred on this sample.
  P                Display the current selection on the secondary
                   plot device as a spectrum. This command will
                   work only if device2 is specified.
 

PARAMETERS

vis
Input visibility dataset to be flagged. No default.
line
This is the normal linetype specification. See the help on "line" for more information. The default is all channels.
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
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
device
PGPLOT plot device/type, which must be interactive. No default.
device2
PGPLOT plot device/type, which must be interactive. This optional plot device will be used to display spectra from the selected region, if requested.
mode
Display ``amplitude'' or ``phase''. By default, ``amplitude'' is selected. For mode=``phase'', the phase is in degrees.
options
Task enrichment parameters. Several can be given, separated by commas. Minimum match is used. Possible values are:
  selgen  Generate a file appropriate for selecting the bad data
          (via a 'select' keyword). The output is two text files
          called 'blflag_flag.select' (for flagging operations),
          and 'blflag_unflag.select' (for unflagging operations).
          Unfortunately, since 'select' does not support the use
          of a 'channel' selection, this option is of limited use,
          but is supplied in case time-based selection is all that
          is required.
  nosrc   Do not cause a break in the display when the source
          changes. Normally PGFLAG puts a gap in the display
          whenever the source changes.
  noapply Do not apply the flagging.
The following options can be used to disable calibration.
  nocal   Do not apply antenna gain calibration.
  nopass  Do not apply bandpass correction.
  nopol   Do not apply polarisation leakage correction.

pgflag.for,v 1.2 2011/03/23 13:45:42 pteuben Exp $


 

Index

NAME
PERSON RESPONSIBLE
CATEGORIES
DESCRIPTION
PARAMETERS

This document was created by man2html, using the manual pages.
Time: 18:35:38 GMT, July 05, 2011