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SOLVE AMPLITUDE

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

  *** THIS HELP HAS NOT BEEN UPDATED FOR THE NGRX ***

  This command fits a mathematical function into the measured  amplitude  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  AMPLITUDE
  for  the  baselines  and bands of interest, specified by the corresponding
  SET commands. The calibration function is kept in memory.   Command  STORE
  AMPLITUDE  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 AMPLITUDE internally and temporarily resets SET AMPLITUDE to SCALED.

  In antenna mode (selected by SET AMPLITUDE 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%. Strong deviations of amplitude closures from 100%
  are an indication of amplitude loss on long baselines, due to phase decor-
  relation  during  the time averaging. The fit then shows strong systematic
  errors; if this occurs, baseline based calibration of the amplitudes might
  be preferred.

  Option /PLOT will plot the fitted 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.  Addition-
      al  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 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: /POLY-
      NOMIAL [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 er-
  rors.


Gildas manager 2011-09-07