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        CLIC\SET SELECTION mode band subband-list [FREQUENCY freqout]
        [/WINDOW fmin fmax [fmin2 fmax2 ...]]

    Choose the type of data selection to be done by command TABLE (to create
    an output UV table).

      - The first argument 'mode' is CONTINUUM or LINE,  to  prepare  single
        channel or multiple channel maps.

      - The second argument is the sideband to be used: UPPER (or USB), LOW-
        ER (or LSB), AVERAGE (or DSB), AUTO or SSB. DSB may be used in  con-
        junction  with  CONTINUUM:  in  this  case,  two separate visibility
        points are written, one for each sideband. DSB used  in  conjunction
        with LINE means that the side band will be selected to match the de-
        sired frequency range (as given in the command TABLE), thus allowing
        to  mix  in  the same table data from USB and LSB, if different fre-
        quency setups have been used in different configurations. AUTO  will
        determine  for  each narrow input whether the receiver tuning is DSB
        or SSB and accordingly select DSB (write a visibility for each side-
        band)  or the signal sideband if SSB.  SSB will write one visibility
        for the signal side band (automatically determined).  This last  two
        options  are useful for continuum only. For LINE, they will just se-
        lect the matching side band as does DSB.

      - The third argument is a subband list.In CONTINUUM mode, subbands are
        averaged,  in  spectral  mode  they are combined to produce a single
        spectrum.  The subband list is given with the same syntax as in  the
        SET SUBBAND command, e.g. "n1 to n3" or "n1 to n3 and n5".

    Example: SET SELECTION CONTINUUM USB C01 AND C03 AND C05 selects contin-
    uum data, USB, and the subbands C01, C03, and C05.

    Arguments "FREQUENCY freqout" are used only for CONTINUUM tables.   They
    define  the  frequency  (in MHz) used for mapping purposes. U and V (for
    each side band in DSB mode) will be scaled to this frequency.   This  is
    intended  to  combine  maps  obtained in continuum at slightly different
    frequencies.  The default for freqout is the actual observing  frequency
    ,  or the frequency used for previous data if data is appended to a pre-
    viously existing table by the TABLE command.

    Option /WINDOW is used to avoid spectral lines when producing a continu-
    um  table  from spectral correlator data. The first two rest frequencies
    (in MHz) give the first frequency window in which data is  to  be  used,
    the next two give the second frequency window, etc....

Gildas manager 2022-01-17