there is an ActiveX function, which I want to call from MATLAB, e.g.
PrintOut([Background], [Append], [Range], [OutputFileName], [From], [To], [Item], [Copies],
According to the Matlab documentation, you can skip optional input arguments by using an empty array instead (i.e. []).
[]
So this would looks like:
hdlActiveX.PrintOut([],needed args,[],needed args);