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SET SELECTION

        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). DSB may be used in conjunction 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 desired frequency  range
        (as  given  in  the command TABLE), thus allowing to mix in the same
        table data from USB and LSB, if different frequency setups have been
        used in different configurations.

      - 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 2011-04-01