SOLVE PHASE

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SOLVE PHASE

            CLIC\SOLVE PHASE [/PLOT] [/BREAK kind time [kind time ...]]
            [/POLYNOMIAL degree] [/WEIGHT] [/RESET]

        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 (SET PHASE CONTINUOUS). The cali-
        bration 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.

        In  antenna mode (selected by SET PHASE ANTENNA), the averaged phase and
        amplitude closures are computed, as well as their  standard  deviations.
        The phase closures should be close to zero, while the amplitude closures
        should be close to 100%.

        Option /PLOT will plot the fitted curve over  the  data.  Option  /RESET
        will reset the calibration curve in memory.

        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.   Addi-
            tional  knots  may  be  introduced with the option "/BREAK kind time
            [kind time ...]"  which  introduces  a  break  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 de-
            tect 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  (de-
            fault 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 er-
        rors.