How to remove the data from a handle class from memory

Question

0 个投票

I feel like an idiot but I don't seem to be able to solve the following problem:

When I define a handle class, how do I destroy it?

Example:

classdef test_class < handle
    properties
        % Lots of data
        data = rand(1e4,1e4);
    end
    methods
        function delete(obj)
            % What do I put here to destroy the object itself: erase the object itself from memory
            % Only "clear all" seems to work
        end
    end
end

Testing this with

x = test_class;
clear x
memory
clear all
memory

shows that the class data is effectively destroyed by clear all.

Does anyone know what code to use in the delete function ??

Thanks for you replies

Olaf

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Follow Question

Answer 1

Ghada Saleh 2015-8-7

在 MATLAB Online 中打开

0 个投票

Hello Olaf,

I understand you want to clear the class definition in the 'delete' method. You can use the following command:

clear classes;

Note that this command issues a warning and does not clear a class of objects if any of those objects still exists after the workspace is cleared. For example, objects can still exist in persistent variables of functions or figure windows. Also, lear classes does not clear a class if its file is locked using the mlock command. No warning is issued in this case.

Also, if you are using MATLAB R2012b or earlier versions, note that there is a bug when using clear classes. This bug is fixed in R2013a.

I hope this helps,

Ghada

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Olaf Bousche 2015-8-13

在 MATLAB Online 中打开

Dear Ghada:

Thanks for your response. The clear classes provide only a partial solution for what I wanted. The problems I had with classes with a lot of data eating all my memory where caused by my misunderstanding on how to uses such classes. When you want to use such classes I should have created a class constructor. The following definition solves the problem:

classdef test_class < handle
    properties
        % Just the property
        data;
    end
    methods
        % Creator goes here
        function obj = test_class()
            obj.data = rand(1e4); % All the data
        end
    end
end

A simple clear or delete command now clears the data.

I got this answer from Matlab support.

Olaf

请先登录，再进行评论。

How to remove the data from a handle class from memory

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

采纳的回答

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

更多回答（0 个）

类别

产品

标签

Community Treasure Hunt

How to remove the data from a handle class from memory

0 个评论 显示 -2更早的评论 隐藏 -2更早的评论

采纳的回答

1 个评论 显示 -1更早的评论 隐藏 -1更早的评论

更多回答（0 个）

类别

产品

标签

另请参阅

Community Treasure Hunt

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

1 个评论
显示 -1更早的评论隐藏 -1更早的评论