modify

MODIFY Modifies an MPTCTRL object

   [ctrl,Idx_orig] = modify(ctrl, action, indices)
   [ctrl,Idx_orig] = modify(ctrl, action, Options)
   [ctrl,Idx_orig] = modify(ctrl, action, indices, Options)

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 DESCRIPTION
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 Modifies a given MPTCTRL object by either removing and adding regions.

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 INPUT
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 ctrl        - explicit controller (an MPTCTRL object)
 action      - what to do:
                 'remove'     - remove selected regions
                 'pick'       - pick a subset of regions
                 'removeflat' - remove flat regions
 indices     - indices of regions to remove/pick
 Options     - additional options structure
   .r_small  - maximal chebychev ball size for detection of a flat region 
               (default: mptOptions.rel_tol)
   .bbox     - minimal bounding box size for detection of a flat region
               (default: mptOptions.rel_tol)

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 OUTPUT                                                                                                    
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 ctrl      - updated MPTCTRL object with given regions removed
 Idx_orig  - corresponding region number in the original partition ctrl