SOLVE PHASE

 

        CLIC\SOLVE   PHASE   [/PLOT]    [/BREAK    ...]     [/POLYNOMIAL...]
    [/WEIGHT]

    This will fit a mathematical function into the measured  phases  of  the
    sources  in  the current index (presumably calibrators).  This data must
    have been selected and plotted in axes :  SET   X   TIME   and   SET   Y
    PHASE  for  the  baselines  and  bands  of  interest,  specified  by the
    corresponding  SET  commands.   Phases  should   be   continuous.    The
    calibration  function  is  kept in memory.  Command STORE should be used
    next to store this function in the header of source observations,  after
    a change in the index to select the appropriate scans.

    SOLVE PHASE internally and temporarily resets  SET  PHASE  to  ABSOLUTE.
    The INTERNAL|EXTERNAL mode is kept to allow determining a phase curve on
    top of an external receiver reference.

    Option /PLOT will plot the fitted phase curve over the data.

    Fitted curves may be of two kinds:

  -  Cubic splines (the default).  By default  knots  are  regularly  spaced
    with   an   interval   between   knots   set  by  the  SET STEP command.
    Additional knots may be introduced with the  option:  /BREAK  kind  time
    [kind  time  ...]  a  break introduced at abscissa 'time' ; 'kind' is an
    integer in the  range 0-3; 0 means that a discontinuity will be present,
    1  that  the  first  derivative  will  be   discontinuous,  and  so  on.
    Several  breaks  may  be introduced; the program will detect an error if
    too   many   breaks  are  introduced,  compared  to  the density of data
    points.

  -  Polynomial curves may  be  used  instead.   For  this  the  option  is:
    /POLYNOMIAL  [degree]  indicating  the degree of the polynomial (default
    0).


    Normally the data points are all assigned the same weight  for  the fit.
    With   option  /WEIGHT,  the data points are weighted according to their
    errors.  Errors computed from the  phase  rms  determined  in  the  data
    compression.