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MINIMIZE

        FIT\MINIMIZE

    Performs a fit of a theoretical profile in the R spectrum using  initial
    values  specified by the command LINES. The profile is determined by the
    METHOD command (GAUSS, SHELL or NH3 lines are currently implemented, and
    a special method, CONTINUUM, may be used for continuum data).

    MINIMIZE  performs  the fit only on the part of the spectrum selected by
    SET MODE X. It also ignores the regions under the masks defined  by  SET
    MASK.

    If  LINES  is 0, an attempt to guess initial values for a single line is
    done by computing the moments of the spectrum.  A first minimisation  is
    performed  using the Simplex technique; the results are improved and the
    uncertainties computed using the Gradient technique. If MINIMIZE did not
    converge,  the  errors  quoted  in  the results are meaningless, and you
    should use command ITERATE to try to do better.

    For CONTINUUM method, although a linear  baseline  is  fitted  with  the
    gaussian,  only  the gaussian parameters are displayed.  If the observa-
    tion was made using beam-switching method and the reference beam appears
    in the drifts, a two-component gauss fit is done using separation speci-
    fied in the data.

    The fitting results are saved in the R% variable, for e.g. reuse in pro-
    cedures:
      Method      Structure
      GAUSS       R%HEAD%GAU%
      SHELL       R%HEAD%SHE%
      NH3/HFS     R%HEAD%HFS%
      ABSORPTION  R%HEAD%ABS%
      CONTINUUM   R%HEAD%POI%
    See  HELP  SET  VARIABLE for the detailed meaning of each component. For
    example, the gaussian fit parameters can be found in:
      Parameter       Variable
      Area            R%HEAD%GAU%RESULT['(ILINE-1)*3+1']
      Error(Area)     R%HEAD%GAU%ERROR['(ILINE-1)*3+1']
      Position        R%HEAD%GAU%RESULT['(ILINE-1)*3+2']
      Error(Position) R%HEAD%GAU%ERROR['(ILINE-1)*3+2']
      Width           R%HEAD%GAU%RESULT['(ILINE-1)*3+3']
      Error(Width)    R%HEAD%GAU%ERROR['(ILINE-1)*3+3']
    where ILINE is the number of one of the  fitted  lines,  between  1  and
    R%HEAD%GAU%NLINE.


Gildas manager 2014-07-01