function varargout = pow2(varargin)

switch class(varargin{1})

    case 'sdpvar'
        varargout{1} = InstantiateElementWise(mfilename,varargin{:});

    case 'char'
        
        operator = CreateBasicOperator('convex','increasing','positive','callback');        
        operator.derivative = @(x)(log(2)*pow2(x));

        varargout{1} = [];
        varargout{2} = operator;
        varargout{3} = varargin{3};

    otherwise
        error(['SDPVAR/' upper(mfilename) ' called with weird argument']);
end