MATLAB Programming

9 Classes and Objects
if isa(name,'portfolio')
p = name;
else
disp([inputname(1) ' is not a portfolio object'])
return
end
otherwise
% create object using specified arguments
p.name = name;
p.totalValue = 0;
for k = 1:length(varargin)
p.indAssets(k) = {varargin{k}};
assetValue = get(p.indAssets{k},'CurrentValue');
p.totalValue = p.totalValue + assetValue;
end
p.accountNumber = '';
p = class(p,'portfolio');
end
Constructor Calling Syntax
The portfolio constructor method can be called in one of three different ways:
• No input arguments — If called with no arguments, it returns an object
with empty fields.
• Inputargumentisanobject—Iftheinputargumentisalreadyaportfolio
object, MATLAB returns the input argument. The isa function checks
for this case.
• More than two input arguments — If there are more than two input
arguments, the constructor assumes the first is the client’s name and the
rest are asset subclass objects. A more thorough implementation would
perform more careful input argument checking, for example, using the isa
function to determine if the arguments are the correct class of objects.
The Portfolio display Method
The portfolio display method lists the contents of each contained object by
calling the object’s display method. It then lists the client name and total
asset value.
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