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        LAS\ACCUMULATE  [/RESAMPLE  [NX  Xref  Xval  Xinc  Unit]]  [/NOCHECK
        LAS\ACCUMULATE /2010

    ACCUMULATE /2010 uses the old (obsolescent) averaging engine (as of year
    2010). No options are allowed in this mode.

    ACCUMULATE  is used to add a pair of spectra together. The T spectrum is
    added to the R spectrum using the current weighting  function  (see  SET
    WEIGHT).  On  return  R contains the sum spectrum, and T the observation
    previously in R. To add more than 2 spectra, you should build  an  index
    and  AVERAGE  it  in a single step instead (this will prevent cumulative
    resamplings, respect the respective weights, and preserve  at  best  the
    noise properties).

    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.


Gildas manager 2014-07-01