MINIMIZE
Keywords: class

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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

- MINIMIZE GAUSSIAN
- MINIMIZE SHELL
- MINIMIZE HFS
- MINIMIZE CONTINUUM
- MINIMIZE /NOCHECK