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MINIMIZE

        FIT\MINIMIZE [/NOCHECK BASELINE]

    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.

    In the fit result output, the fit is said:
      - "optimistic" if R%HEAD%GAU%RMS_BASE > R%HEAD%GAU%RMS_LINE * 1.5,
      - "bad" if R%HEAD%GAU%RMS_BASE < R%HEAD%GAU%RMS_LINE / 1.5
    where  RMS_LINE  and  RMS_BASE  are  the  RMS  of  residuals on the line
    range(s) and the remaining base, respectively. This  comment  is  purely
    informative.

    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 subtopic for details.


Subsections

Gildas manager 2024-04-18