MS Options — Flagging Options

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7.4.1.4 MS Options — Flagging Options

These options allow you to edit (flag or unflag) MS data. The Point Tool and Rectangle Region Mouse Tools (§ 7.2.3) are used on the display to select the area to edit. When using the Rectangle Region tool, double-click inside the selected rectangle to confirm the edit.

The options below determine how edits will be applied.

Show Flagged Regions...
You have the option to display flagged regions in the background color (as in TVFLG) or to highlight them with color. In the former case, flagged regions look just like regions of no data. With the (default) color option, flags are shown in shades of blue: darker blue for flags already saved to disk, lighter blue for new flags not yet saved; regions with no data will be shown in black.
Flag or Unflag
This setting determines whether selected regions will be flagged or unflagged. This does not affect previous edits; it only determines the effect which later edits will have. Both flagging and unflagging edits can be accumulated and then saved in one pass through the MS.
Flag/Unflag All...
These flagging extent checkboxes allow you to extend your edit over any of the five data axes. For example, to flag all the data in a given time range, you would check all the axes except Time, and then select the desired time range with the Rectangle Region mouse tool. Such edits will extend along the corresponding axes over the entire selected MS (whether loaded into memory or not) and optionally over unselected portions of the MS as well (Use Entire MS, below). Use care in selecting edit extents to assure that you’re editing all the data you wish to edit.
Flag/Unflag Entire Antenna?
This control can be used to extend subsequent edits to all baselines which include the desired antenna[s]. For example, if you set this item to ’Yes’ and then click the point tool on a visibility position with baseline 3-19, the edit would extend over baselines 0-3, 1-3, 2-3, 3-3, 3-4, ... 3-nAntennas-1. Note that the second antenna of the selection (19) is irrelevant here – you can click anywhere within the ’Antenna 3 block’, i.e., where the first antenna number is 3, to select all baselines which include antenna 3.
This item controls the edit extent only along the baseline axis. If you wish to flag all the data for a given antenna, you must still check the boxes to flag all Times, Channels, Polarizations and Spectral Windows. There would be no point, however, in activating both this item and the ’Flag All Baselines’ checkbox. You can flag an antenna in a limited range of times, etc., by using the appropriate checkboxes and selecting a rectangular region of visibilities with the mouse.
Note: You do not need to include the entire ’antenna block’ in your rectangle (and you may stray into the next antenna if you try). Anywhere within the block will work. To flag higher-numbered antennas, it often helps to zoom in.
Undo Last Edit
Undo All Edits
The ’Undo’ buttons do the expected thing: completely undo the effect of the last edit (or all unsaved edits). Please note, however, that only unsaved edits can be undone here; there is no ability to revert to the flagging state at the start of the session once flags have been saved to disk (unless you have previously saved a ’flag version’. The flag version tool is not available through the viewer directly).
Use Entire MS When Saving Edits?
”Yes” means that saving the edits will flag/unflag over the entire MS, including fields (and possibly spectral windows) which are not currently selected for viewing. Specifically, data within time range(s) you swept out with the mouse (even for unselected fields) will be edited.
In addition, if ”Flag/Unflag All...” boxes were checked, such edits will extend throughout the MS. Note that only unselected times (fields) can be edited without checking extent boxes for the edits as well. Unselected spectral windows, e.g., will not be edited unless the edit also has ”Flag/Unflag All Spectral Windows” checked.
Warning: Beware of checking ”All Spectral Windows” unless you have also checked ”All Channels” or turned ”Entire MS” off; channel edits appropriate to the selected spectral windows may not be appropriate to unselected ones. Set ”Use Entire MS” to”No” if your edits need to apply only to the portion of the MS you have selected for viewing. Edits can often be saved significantly faster this way as well.
Also note that checkboxes apply to individual edits, and must be checked before making the edit with the mouse. ”Use Entire MS”, on the other hand, applies to all the edits saved at one time, and must be set as desired before pressing ”Save Edits”.
Save Edits
MS editing works like a text editor in that you see all of your edits immediately, but nothing is committed to disk until you press ’Save Edits’. Feel free to experiment with all the other controls; nothing but ’Save Edits’ will alter your MS on disk. As mentioned previously, however, there is no way to undo your edits once they are saved, except by manually entering the reverse edits (or restoring a previously-saved ’flag version’).
Also, you must save (or discard) your edits before changing the MS selections. If edits are pending, the selection change will not be allowed, and a warning will appear on the console.
If you close the MS in the viewer, unsaved edits are simply discarded, without prior warning. It’s important, therefore, to remember to save them yourself. You can distinguish unsaved flags (when using the ’Flags In Color’ option), because they are in a lighter shade of blue.
The program must make a pass through the MS on disk to save the edits. This can take a little time; progress is shown in the console window.

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