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exc ... neb [number_of_border_nodes]
Smoothes like grp exc but , but will not smooth at the border (no exclude points at border). Default is 1 node, but neb number_of_border_nodes will set the no_smoothing_zone higher. Thus with this argument one can extract a part of a grid and smooth it with grp exc neb and insert it into the grid (using rep lo grid) without having any unpleasant transition zone where the grid is inserted.
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