% gui.stripchart
% A class for plotting data in a continuous scroll.
%
% C = gui.stripchart() creates an axes in the current figure for
% plotting a stripchart. To add new data to the plot, use the method
% UPDATE. If the figure or axes is deleted, the stripchart object C is
% automatically deleted.
%
% C = gui.stripchart(AX) uses the axes AX for the stripchart. This axes
% handle can be retrieved later with the property UiAxes.
%
% C = gui.stripchart(AX, NUMPOINTS) uses the axes AX for the stripchart,
% and sets the NumPoints property (the total width of the stripchart) to
% NUMPOINTS.
%
% Sample usage:
% c = gui.stripchart;
% for i=1:300
% data = rand(1) * sin(0:0.1:2*pi);
% c.update(data);
% pause(0.01);
% end
%
% Also see:
% <a href="matlab:help gui.stripchart.update">update</a> (method)
% <a href="matlab:help gui.daqinput">gui.daqinput</a>
% Copyright 2009 The MathWorks, Inc.
classdef stripchart < handle
properties(GetAccess=public, SetAccess=private)
% UiAxes
% The handle to the stripchart axes. This property can be
% used to adjust the axes appearance (deleting the axes will
% automatically delete the stripchart object as well).
%
% Sample usage:
% c = gui.stripchart;
% c.update(sin(0:0.01:20));
% set(c.UiAxes, 'Color', 'k');
% grid(c.UiAxes, 'on');
UiAxes
% UiLine
% The handle to the stripchart plot. This property can be
% used to adjust the line appearance (deleting the line will
% automatically delete the stripchart object as well).
%
% Sample usage:
% c = gui.stripchart;
% c.update(sin(0:0.01:20));
% set(c.UiAxes, 'Color', 'k');
% set(c.UiLine, 'Color', 'g', 'LineWidth', 1);
%
UiLine
% NumPoints
% The total number of points in the stripchart. When N new points
% are added to the stripchart (using the UPDATE method), the N
% oldest points are deleted. By default, NumPoints is 4096.
%
% The NumPoints property is automatically increased in certain
% conditions (see the <a href="matlab:help gui.stripchart.update">update</a> method).
NumPoints
end
properties(GetAccess=public,SetAccess=private)
% X
% The current x-axis values for the entire stripchart (a
% vector of length NumPoints).
X
% Y
% The current y-axis values for the entire stripchart (a
% vector of length NumPoints).
Y
end
methods
function obj = stripchart(hAxes, numPoints)
if ~exist('hAxes', 'var')
hAxes = gca;
end
if ~exist('numPoints', 'var')
numPoints = 4096;
end
if ~(ishandle(hAxes) && strcmp(get(hAxes,'type'),'axes'))
throw(MException('stripchart:InvalidAxes', 'Invalid axes handle'));
end
obj.UiAxes = hAxes;
obj.NumPoints = numPoints;
% don't initialize X (we don't know whether we'll be using
% samples or time ).
obj.X = [];
obj.Y = [];
obj.UiLine = plot(nan, nan, 'parent', hAxes);
set(obj.UiLine, 'DeleteFcn', @(h,e) delete(obj));
end
function update(obj, x, y)
% update gui.stripchart method
%
% OBJ.update(x,y) updates the stripchart OBJ with the data
% points specified by x and y (vectors of length N). x is
% assumed to be monotonically increasing.
%
% OBJ.update(y) updates the y-axis of the stripchart OBJ
% with the data in y (a vector of length N). The x-axis is
% unchanged.
%
% Note:
% 1) If N <= NumPoints, the N oldest points in the stripchart
% are deleted. If N > NumPoints, then NumPoints is
% increased to match the new data.
% 2) Callers should consistently use either update(x,y) or
% update(y). If calls are intermingled, the x-axis of the
% stripchart may change unexpectedly.
% 3) When using update(x,y), successively calls should have
% monotonically increasing values of x. Otherwise, the
% x-axis of the stripchart may change unexpectedly.
%
% Sample usage:
% t = 0:0.01:40;
% c1 = gui.stripchart(subplot(2,1,1), 500);
% for i=1:200:length(t)-1
% c1.update( sin(t(i:i+200)) );
% pause(0.1);
% end
%
% c2 = gui.stripchart(subplot(2,1,2), 500);
% for i=1:200:length(t)-1
% c2.update( t(i:i+200), sin(t(i:i+200)) );
% pause(0.1);
% end
%
% Also see:
% <a href="matlab:help gui.stripchart.UiLine">UiLine</a> (property)
% <a href="matlab:help gui.stripchart.UiAxes">UiAxes</a> (property)
if ~exist('y', 'var')
% set only the y-axis
if isempty(obj.X)
obj.X = (1:obj.NumPoints).';
obj.Y = zeros(obj.NumPoints,1);
set(obj.UiLine, 'xdata', obj.X, 'ydata', obj.Y);
set(obj.UiAxes, 'xlim', [1 obj.NumPoints]);
end
y = x;
ny=numel(y);
obj.Y = [obj.Y(ny+1:obj.NumPoints) ; y(:)];
if ny > obj.NumPoints
obj.NumPoints = ny;
obj.X = (1:obj.NumPoints).';
set(obj.UiLine, 'xdata', obj.X, 'ydata', obj.Y);
set(obj.UiAxes, 'xlim', [1 obj.NumPoints]);
else
set(obj.UiLine, 'ydata', obj.Y);
end
else
% set both X and Y
nx=numel(x); ny=numel(y);
if nx ~= ny
throw(MException('stripchart:InvalidXYData', 'x and y vectors must have same length'));
end
% reset X and Y if just starting, or if time hasn't
% increased monotonically
if isempty(obj.X) || (x(1) < obj.X(end))
obj.X = zeros(obj.NumPoints,1);
obj.Y = zeros(obj.NumPoints,1);
end
obj.X = [obj.X(nx+1:obj.NumPoints) ; x(:)];
obj.Y = [obj.Y(ny+1:obj.NumPoints) ; y(:)];
if ny > obj.NumPoints
obj.NumPoints = ny;
end
set(obj.UiLine, 'xdata', obj.X, 'ydata', obj.Y);
xlim = obj.X([1 end]);
if ~any(isnan(xlim)) && xlim(2) >= xlim(1)
set(obj.UiAxes, 'xlim', xlim);
end
end
end
end % of methods
end
