Flag extension in plotxy

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3.3.2.11 Flag extension in plotxy

Flag extension is controlled using extendflag=T and its sub-parameters:

extendflag          =   True    #  Have flagging extend to other data points?
     extendcorr     =     ’’    #  flagging correlation extension type
     extendchan     =     ’’    #  flagging channel extension type
     extendspw      =     ’’    #  flagging spectral window extension type
     extendant      =     ’’    #  flagging antenna extension type
     extendtime     =     ’’    #  flagging time extension type

The use of extendflag enables the user to plot a subset of the data and extend the flagging to a wider set.

ALERT: Using the extendflag options will greatly slow down the flagging in plotxy. You will see a long delay after hitting the Flag button, with lots of logger messages as it goes through each flag. Fixing this requires a refactoring of plotxy which is underway starting in Patch 4 development.

Setting extendchan=’all’ will extend the flagging to other channels in the same spw as the displayed point. For example, if spw=’0:0’ and channel 0 is displayed, then flagging will extend to all channels in spw 0.

The extendcorr sub-parameter will extend the flagging beyond the correlations displayed. If extendcorr=’all’, then all correlations will be flagged, e.g. with RR displayed RR,RL,LR,LL will be flagged. If extendcorr=’half’, then the extension will be to those correlations in common with that show, e.g. with RR displayed then RR,RL,LR will be flagged.

Setting extendspw=’all’ will extend the flagging to all other spw for the selection. Using the same example as above, with spw=’0:0’ displayed, then channel 0 in ALL spw will be flagged. Note that use of extendspw could result in unintended behavior if the spw have different numbers of channels, or if it is used in conjunction with extendchan.

WARNING: use of the following options, particularly in conjunction with other flag extensions, may lead to deletion of much more data than desired. Be careful!

Setting extendant=’all’ will extend the flagging to all baselines that have antennas in common with those displayed and marked. For example, if antenna=’1&2’ is shown, then ALL baselines to BOTH antennas 1 and 2 will be flagged. Currently, there is no option to extend the flag to ONLY baselines to the first (or second) antenna in a displayed pair, so it is better to use flagdata2 to remove specific antennas.

Setting extendtime=’all’ will extend the flagging to all times matching the other selection or extension for the data in the marked region.

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