Is constructor method the only method that creates an object in a class definition?

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Yves 2017-12-11

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评论： Yves 2017-12-11

Another way to ask this question is: how do I create a value class object as the output of a handle class ordinary method? For example,

classdef handleClassA < handle
    properties
    end
    methods
        function obj = handleClassA(varargin)
            ...
        end
        function ValueClassobj2 = unknownmethod(handleClassAobj, ValueClassobj1)
            ValueClassobj2.property1 = ...
            some_sort_function(handleClassAobj.property3, ValueClassobj1.property1);
            ...
        end
    end
end

If I do it the above way, the output is a struct with field property1, etc., not a object of a class.

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Steven Lord 2017-12-11

digraph is the constructor for the digraph class included in MATLAB since release R2015b.

In this simple example createDigraph only calls the constructor for the digraph class with a sample matrix returned from the bucky function (also included in MATLAB.)

In a "real world" scenario the myHandleClass object would probably have properties that the createDigraph method would use to compute the matrix with which you call the digraph constructor.

Yves 2017-12-11

Thx, Steven.

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采纳的回答

Matt J 2017-12-11

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编辑：Matt J 2017-12-11

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I think you are trying to do,

    function ValueClassobj2 = unknownmethod(handleClassAobj, ValueClassobj1)
         ValueClassobj2 = ValueClassobj1; %clone of obj1
      ValueClassobj2.property1 = ...
     some_sort_function(handleClassAobj.property3, ValueClassobj1.property1);
    ...
    end

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Yves 2017-12-11

编辑：Matt J 2017-12-11

在 MATLAB Online 中打开

Matt, if I understand you correctly, the statement

ValueClassobj2 = ValueClassobj1;

creates the object "ValueClassobj2", in the same class as "ValueClassobj1". Correct?

What if I don't have a same class object as "ValueClassobj2" that I wanted to create, but an array of input variables? Will I still be able to define "unknownmethod" as a method of currect class "handleClassAobj", to create the object "ValueClassobj2"?

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