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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),  LOWER
      (or  LSB),  AVERAGE (or DSB), AUTO or SSB. DSB may be used in conjunc-
      tion 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  fre-
      quency  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. AUTO will determine for
      each narrow input whether the receiver tuning is DSB or  SSB  and  ac-
      cordingly  select  DSB  (write  a visibility for each sideband) or the
      signal sideband if SSB.  SSB will write one visibility for the  signal
      side  band (automatically determined).  This last two options are use-
      ful for continuum only. For LINE, they will just select  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 spec-
      trum.   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 continuum
  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 fre-
  quency used for previous data if data is appended to a previously existing
  table by the TABLE command.

  Option  /WINDOW is used to avoid spectral lines when producing a continuum
  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 2011-09-07