function varargout = atan2(varargin)

switch class(varargin{1})

    case 'sdpvar' 
        varargout{1} = yalmip('define','atan2_internal',[varargin{:}]);        

    case 'char'

        X = varargin{3};

        varargout{1} = [];
        varargout{2} = struct('convexity','none','monotonicity','none','definiteness','none','model','exact');
        varargout{3} = [X(:)];
    otherwise
        error('SDPVAR/atan2 called with CHAR argument?');
end