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ACCUMULATE

        LAS\ACCUMULATE  [/RESAMPLE  [NX  Xref  Xval  Xinc  Unit]]  [/NOCHECK
    [SOURCE|POSITION|LINE|SPECTROSCOPY|CALIBRATION|SWITCHING]]      [/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 add
    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 added channel by channel by default, if possible. Else
    the option /RESAMPLE must be invoked (see subtopic for details).

    ACCUMULATE checks the consistency between R and T, in particular the po-
    sitional  coincidence  and  calibration  homogeneity  according  to  SET
    [NO]MATCH and SET CALIBRATION respectively. The option  /NOCHECK  allows
    to  disable  some (using one or several names) or all (no name given) of
    these checks.

    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 2018-02-24