Flagging CABB data
Posted: Mon Feb 08, 2010 12:18 pm
Flagging data from CABB can be quite difficult as there are a large number of channels and the data volume is great. MIRIAD has undergone some improvements recently to assist users while flagging CABB data.
The routine blflag has been improved, and a new option made available: nofqaver. Using this option means that blflag will not average all channels together before displaying them, so now you can use the same point-and-click flagging as before with a large bandwidth where only narrowband interference is present. You can also now specify channel as one of the blflag axes.
The new routine pgflag is a replacement for the obsolete tvflag, which had the significant problem of not being usable on screens with more than an 8-bit colour depth. pgflag uses standard PGPLOT displays, and allows you to flag via a familiar waterfall plot of channel vs time. All of the actions of tvflag are replicated, along with some new actions, although they are now all controlled through keypresses instead of an on-screen menu, so be sure to read the MIRIAD man page for pgflag before beginning.
There is also an automatic flagger in development by Emil Lenc based on pieflag. Contact Emil if you'd like to know more (and hopefully he will reply to this post with a description of his flagger!)
The routine blflag has been improved, and a new option made available: nofqaver. Using this option means that blflag will not average all channels together before displaying them, so now you can use the same point-and-click flagging as before with a large bandwidth where only narrowband interference is present. You can also now specify channel as one of the blflag axes.
The new routine pgflag is a replacement for the obsolete tvflag, which had the significant problem of not being usable on screens with more than an 8-bit colour depth. pgflag uses standard PGPLOT displays, and allows you to flag via a familiar waterfall plot of channel vs time. All of the actions of tvflag are replicated, along with some new actions, although they are now all controlled through keypresses instead of an on-screen menu, so be sure to read the MIRIAD man page for pgflag before beginning.
There is also an automatic flagger in development by Emil Lenc based on pieflag. Contact Emil if you'd like to know more (and hopefully he will reply to this post with a description of his flagger!)