If there are more than "excess" elements of the cell_ids() vector that are allocated but unused, reallocates the array to eliminate the excess space. This reduces memory usage when many cell unions need to be held in memory at once.
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If there are more than "excess" elements of the cell_ids() vector that are allocated but unused, reallocates the array to eliminate the excess space. This reduces memory usage when many cell unions need to be held in memory at once.