Matlab : Object array indexing by property -

in matlab, create array of objects can pick element 1 of unique property while keeping same behavior normal indexing.

here class:

classdef myclass < dynamicprops      properties         name = '';         values     end      methods         function obj = myclass(name,values)             if nargin > 0                 obj.name = name;                 obj.values = values;             end         end     end end 

lets consider following array :

>> a(1) = myclass('one'  ,[1:10]); >> a(2) = myclass('two'  ,[2:20]); >> a(3) = myclass('three',[3:30]); 

the easiest way directly acess values of element :

>> a(1).values ans =  1     2     3     4     5     6     7     8     9    10 

but call elements of array name not index, while keeping ability have direct access values :

>> % /!\ intended behavior, not real result >> a('two').values(end-2:end) * 3 ans =     54    57    60 

i une two = findobj(a,'name','two'); two.values(end-2:end) * 3 it's not convinient.

i've tried setting custom subsref method object , works quite lose indexing features.

i got intended behavior following method :

function out = subsref(obj,s)     if strcmpi(s(1).type,'()') && ischar(s(1).subs{1})         found = findobj(obj,'name',s(1).subs{1});         if ~numel(found)             error(['object name ''' s(1).subs{1} ''' not found.'])         end         if numel(s) == 1             out = found(1);         else             out = builtin('subsref',found(1),s(2:end));         end     else         out = builtin('subsref',obj,s);     end end 

but can't names/values [a.values] or {a.name}. matlab returns :

error using myclass/subsref many output arguments. 

and might lose other indexing features well.

is there better solution problem ? appreciated.

you can use varargout in subsref support getting list of values of property values:

function varargout = subsref(obj,s)     if strcmpi(s(1).type,'()') && ischar(s(1).subs{1}) && ...         ~strcmp(s(1).subs{1},':')         found = findobj(obj,'name',s(1).subs{1});         if ~numel(found)             error(['object name ''' s(1).subs{1} ''' not found.'])         end         if numel(s) == 1             varargout{1} = found(1);         else             varargout{1} = builtin('subsref',found(1),s(2:end));         end     else         [varargout{1:nargout}] = builtin('subsref',obj,s);     end end 

note added ~strcmp(s(1).subs{1},':') condition in first if support a(:) indexing.

one other consideration see how handle multiple strings:

a('one','two'); 

or mixed types:

a('one',3:end); 

these more corner cases, consider.