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        CLIC\TABLE Name [OLD|NEW] [/COMPRESS tmax uvmax]
        [/RESAMPLE nc ref val inc code shape width]  [/FFT]
        [/FREQUENCY name rest-freq] [/DROP  n1 n2]

    This command will create an UV data Table from the  current  index.   is
    not given, the most recently created table will be extended.  Next argu-
    ment may be OLD (default value if not specified) to extend and  existing
    table, or NEW to create a new table.

    The  bands and subbands used must have been given by the command SET SE-
    LECTION. The weighting mode can be modified by the command SET WEIGHTS.

    TABLE /RESAMPLE nc ref val inc code [shape width /FFT]

        Option /RESAMPLE enables to resample data on  a  new  spectral  grid
        (for  line  data).  'nc' is the output number of channels, 'ref' the
        reference channel, 'val' the value of velocity or  frequency  offset
        (with respect to the rest frequency) at the reference channel, 'inc'
        the resolution, 'code' is "V" if the value 'val' and the  resolution
        'inc' are in velocity units, "F" for frequency units.

        The  reference channel thus corresponds to the given 'val' velocity,
        or to the offset 'val' in MHz from the rest frequency present in the
        header or modified by option /FREQUENCY.

        Resampling  is done by default through linear interpolation of input
        channel data. Resampling may also be done  (using  option  /FFT)  in
        Fourier space by cut-off or extrapolation (by zeroes) of the Fourier
        components, after deconvolution by the channel response of the  cor-
        relator  (due to on-line apodization), and followed by reconvolution
        to produce frequency channels of the given 'shape' and 'width'.  Al-
        lowed shapes are:
          TBox = a box in delay space (unapodized correlator)
          Ppar  =  a  parabola in delay space (apodized correlator) (the de-
          FBox = a box in frequency space (square filter)
          FTri = a triangle in frequency space (Hanning smoothed square fil-
        The  width  is the channel width in units of channel separation (de-
        fault 1).

        Option /FFT is not recommended when joining  together  several  sub-
        bands  to  produce a single spectrum, with a limited number of broad
        channels.  In those cases using the FFT  could  produce  a  spectrum
        with "holes" at the points between subbands with limited overlap.

    TABLE /FREQUENCY  name rest-freq

        Option  /FREQUENCY  is  used to redefine the rest frequency (in MHz)
        and line name for the output table.  The velocity scale is  computed
        accordingly.   This  rest frequency will correspond to the reference
        channel in option RESAMPLE.


        When processing each scan, CLIC checks whether a number of  position
        parameters  are  consistent  with those defined in the table header.
        Option /NOCHECK allows to switch off this checking.   Arguments  can
        be  given  to  switch  off only part of the parameters (SOURCE name,
        POINTING direction, PHASE center, EPOCH of coordinates). This option
        is  intended for building tables with inconsistent parameters (typi-
        cal exemple is a different source name...). It is  potentially  dan-
        gerous and is to be used with caution.


        Option  /DROP enables to drop the first 'n1' and last 'n2'  channels
        in each subband of the OLD spectral correlator. For the NEW spectral
        correlator  (data  taken  since  summer 1992), it is replaced by the
        commands SET GIBBS and SET DROP.

    TABLE /COMPRESS tmax uvmax

        Option /COMPRESS is used to compress the data  before  writing   the
        table.    This  works like the COMPRESS command, but no intermediate
        file is written. Very seldom used.


Gildas manager 2018-08-18