MATLAB Object-Oriented Programming

The following definition of the TemperatureData class implements a specialized version

of plot to graph temperature data. The class plot method supports a variable number of

input arguments to allow an axes handle as the first argument:

plot(obj)

plot(ax,obj)

obj is an instance of the TemperatureData class and ax is an axes handle.

MATLAB calls the plot method in both cases because the TemperatureData class

specifies the matlab.graphics.axis.Axes as inferior.

classdef (InferiorClasses = {?matlab.graphics.axis.Axes}) TemperatureData

properties

Time

Temperature

end

methods

function obj = TemperatureData(x,y)

obj.Time = x;

obj.Temperature = y;

end

function plot(varargin)

if nargin == 1

obj = varargin{1};

plot(obj.Time,obj.Temperature)

elseif nargin == 2

ax = varargin{1};

obj = varargin{2};

plot(ax,obj.Time,obj.Temperature)

elseif nargin > 2

ax = varargin{1};

obj = varargin{2};

plot(ax,obj.Time,obj.Temperature,varargin{3:end})

end

datetick('x')

xlabel('Time')

ylabel('Temperature')

end

end

end

The following call to plot dispatches to the TemperatureData plot method, not the

built-in plot function, because the TemperatureData object is dominant over the axes

object.

x = 1:10;

y = rand(1,10)*100;

ax = axes;

td = TemperatureData(x,y);

plot(ax,td)

9 Methods — Defining Class Operations