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ACCUMULATE

        LAS\ACCUMULATE [/NEW]

    ACCUMULATE /NEW uses the new averaging engine. See subtopic for details.

    ACCUMULATE is used to integrate step by step  an  ensemble  of  spectra.
    The  T  spectrum  is added to the R spectrum with the current weights. R
    thus contains the current sum, and T the last sum. As  command  AVERAGE,
    ACCUMULATE  checks  for the positional coincidence and calibration homo-
    geneity according to SET MATCH and SET CALIBRATION respectively. Aligne-
    ment  of  spectra is checked according to SET ALIGN command. Accumulated
    spectra may have different spectral resolution. In this latter case, the
    final spectrum has the coarsest resolution of the two input spectra, and
    each channel will be the weighted average of the average values of  each
    spectrum  in  the resulting channel. It is however preferable to accumu-
    late spectra which have the same resolution.

    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  spec-
    tra.

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


Subsections

Gildas manager 2011-09-07