function hold(varargin)

%HOLD   Hold current graph

%   HOLD ON holds the current plot and all axis properties, including 

%   the current color and linestyle, so that subsequent graphing commands

%   add to the existing graph without resetting the color and linestyle.

%   HOLD OFF returns to the default mode whereby PLOT commands erase 

%   the previous plots and reset all axis properties before drawing 

%   new plots.

%   HOLD, by itself, toggles the hold state.

%   HOLD does not affect axis autoranging properties.

%

%   HOLD ALL is the same as HOLD ON. This syntax will be removed in 

%   a future release. Use HOLD ON instead.

%

%   HOLD(AX,...) applies the command to the Axes object AX.

%

%   Algorithm note:

%   HOLD ON sets the NextPlot property of the current figure and

%   axes to "add".

%   HOLD OFF sets the NextPlot property of the current axes to

%   "replace".

%

%   See also ISHOLD, NEWPLOT, FIGURE, AXES.

%   Copyright 1984-2019 The MathWorks, Inc.

% Parse possible Axes input

narginchk(0,2); 

isaxarr=matlab.graphics.chart.internal.objArrayDispatch(@hold,varargin{:}); 

if isaxarr 

    return

end 

% look for leading axes (must not be a vector of handles)

[ax,args,nargs] = axescheck(varargin{:}); 

% If "ax", returned from axescheck is empty,

% then one of the following cases is true: 

%   1. "ax" object was not passed in.

%   2. Invalid value for "ax" was passed in.

%   3. "ax" corresponds to a stand-alone chart.

if isempty(ax) 

    % if the ax is a standalone chart

    if nargs>0 && isa(args{1},'matlab.graphics.chart.Chart') 

        ax = args{1};

    elseif nargin == 2 

        % If 2 args were passed in and first argument is not

        % an axes object or a stand-alone chart, then throw an 

        % error.

        error(message('MATLAB:hold:InvalidFirstArg'));

    else  

        ax = gca; 

    end     

end 

if isa(ax,'matlab.graphics.chart.Chart')             

    error(message('MATLAB:hold:UnsupportedCurrentAxes',ax.Type));

end 

matlab.graphics.internal.markFigure(ax); 

fig = get(ax,'Parent'); 

if ~strcmp(get(fig,'Type'),'figure') 

  fig = ancestor(fig,'figure');

end 

if ~isempty(args) 

    opt_hold_state = args{1}; 

end 

nexta = get(ax,'NextPlot'); 

nextf = get(fig,'NextPlot'); 

hold_state = strcmp(nexta,'add') && strcmp(nextf,'add'); 

replace_state = 'replace'; 

if isa(ax,'matlab.ui.control.UIAxes') 

    replace_state = 'replacechildren';

end 

if(nargs == 0) 

    if(hold_state)

        set(ax,'NextPlot',replace_state);

        disp(getString(message('MATLAB:hold:CurrentPlotReleased')));

    else

        set(fig,'NextPlot','add');

        set(ax,'NextPlot', 'add');

        disp(getString(message('MATLAB:hold:CurrentPlotHeld')));

    end

elseif(strcmpi(opt_hold_state, 'on')) 

    set(fig,'NextPlot','add'); 

    set(ax,'NextPlot','add'); 

elseif(strcmpi(opt_hold_state, 'off'))

    set(ax,'NextPlot', replace_state);

elseif(strcmpi(opt_hold_state, 'all'))

    set(fig,'NextPlot','add');

    set(ax,'NextPlot','add');

else

    error(message('MATLAB:hold:UnknownOption'));

end