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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 2014-07-01