The default set function for properties works on scalar objects only, but you can write your own functions (and any other function you overload or write yourself) to support vectors (or even matrices) of objects which you then act on.
Then your code above should work fine. I don't tend to do this myself except in a few places because it is a lot of effort supporting vectors of objects in all functions, but it can be useful.
You can do this, though it just moves the for loop inside the class:
classdefMyClass < handle
properties
Value
end
methods
functionset.Value( objArray, value )
validateattributes( objArray, {'MyClass'}, {'vector'} )
validateattributes( value, {'numeric'}, {'scalar'} )
fori = 1:numel( objArray )
objArray(i).Value = value;
end
end
end
end
m(4) = MyClass;
m.Value = 7;
It quickly gets messy from a design perspective though because then you start asking yourself 'Should I also support a vector of values so that I can set the value of 10 objects to each value of an array of 10 numbers?'. And the code soon starts to get very complicated.
The plus operator could be similarly overloaded:
functionobjArray = plus( objArray, value )
validateattributes( objArray, {'MyClass'}, {'vector'} )
validateattributes( value, {'numeric'}, {'scalar'} )
fori = 1:numel( objArray )
objArray(i).Value = objArray(i).Value + value;
end
end
or something similar. Again though you have the questions of what you support because the standard + operator supports more than just adding a scalar to an array (as well as being symmetric, but that is another matter entirely).
Section 17-45 of the
Matlab OOP bible
covers other ways to overload the plus operator with a double operator overload also, but the class needs to be basically a wrapper for one main value property for this to make much sense. Just adding 7 to an arbitrary class full of properties doesn't really have an obvious meaning.
Even the simple early example in 2-6 to 2-7 of that linked document shows how quickly design question can start to arise from relatively simple overloads. In that example a plus operator is overloaded that simply adds the 'Value' or one class to the 'Value' of another. That is fair enough, but the output is a double. Personally I would expect that if I added two of those 'BasicClass' objects together I would end up with a BasicClass object as my output, containing the summed values of the two inputs, rather than just a raw double.
