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ACCUMULATE

        LAS\ACCUMULATE  [/RESAMPLE  [NX Xref Xval Xinc Unit]] [/NOCHECK Arg1
    ... ArgN]] [/WEIGHT TIME|SIGMA|EQUAL|ASSOCIATED]

    ACCUMULATE is used to add a pair of spectra together. The T spectrum  is
    added  to  the  R spectrum using the specified (/WEIGHT) or current (SET
    WEIGHT) weighting function (see HELP SET WEIGHT for details).  To  stack
    more  than 2 spectra, you should build an index and AVERAGE it in a sin-
    gle step instead (this will prevent cumulative resamplings, respect  the
    respective weights, and preserve at best the noise properties).

    On  return R contains the sum spectrum, and T the observation previously
    in R. If /WEIGHT or SET WEIGHT is ASSOCIATED (see HELP  SET  WEIGHT  for
    details), the weight array of the sum spectrum is saved in the associat-
    ed array named W.

    The spectra are stacked channel by channel by default, if possible. Else
    the option /RESAMPLE must be invoked (see subtopic for details).

    For  EQUAL  weights, ACCUMULATE computes the sum of the two spectra, al-
    lowing addition of an ensemble of spectra after division  by  the  total
    number of spectra. For other weightings, ACCUMULATE computes the average
    of the two spectra.

    ACCUMULATE also works on Continuum drift. The alignement may be  Channel
    or Position in this case.


Subsections

Gildas manager 2018-08-15