MATLAB Object-Oriented Programming

statement implements all indexing expressions that begin with that first-level type of

indexing.

The methods must implement all indexing expressions that the class supports. If you do

not customize a particular type of indexing, call the built-in function to handle that

expression.

Use the length of the indexing structure array and indexing type define conditional

statements for compound indexing expressions.

Code Framework for subsref Method

The following framework for the subsref method shows how to use information in the

indexing structure in conditional statements. Your application can involve other

expression not shown here.

function varargout = subsref(obj,s)

switch s(1).type

case '.'

if length(s) == 1

% Implement obj.PropertyName

...

elseif length(s) == 2 && strcmp(s(2).type,'()')

% Implement obj.PropertyName(indices)

...

else

[varargout{1:nargout}] = builtin('subsref',obj,s);

end

case '()'

if length(s) == 1

% Implement obj(indices)

...

elseif length(s) == 2 && strcmp(s(2).type,'.')

% Implement obj(ind).PropertyName

...

elseif length(s) == 3 && strcmp(s(2).type,'.') && strcmp(s(3).type,'()')

% Implement obj(indices).PropertyName(indices)

...

else

% Use built-in for any other expression

[varargout{1:nargout}] = builtin('subsref',obj,s);

end

case '{}'

if length(s) == 1

% Implement obj{indices}

...

elseif length(s) == 2 && strcmp(s(2).type,'.')

% Implement obj{indices}.PropertyName

...

else

% Use built-in for any other expression

17 Specialize Object Behavior