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TABLE_MARGINALIZE

        TABLE_MARGINALIZE

    This  taks  is used to project (marginalize) a table of N+1 columns, one
    of which is contains the value of a function of the N others, onto a ta-
    ble of 3 columns, containing the "marginalized" value of the function of
    only 2 parameters, columns noted X,Y hereafter.  The table is assumed to
    be regularly spaced in (X,Y) values in this current version.

    This  process  is  often needed in multi-parameter minimization, e.g. to
    derive a 2-D Chi^2 surface from an (N-1)-D hypersurface (or  equivalent-
    lyfor a Likelihood distribution).

    To  derive a single value from the N-2 values for each (X,Y) pair, a re-
    duction operation is required. The available operations are MIN  (appro-
    priate  for Chi^2 projection), MAX (appropriate for Likelihood) MEAN and
    SUM.



Gildas manager 2020-12-02