Functions returning part of N-D data

Question

Thomas 2024-7-18，18:56

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2138576-functions-returning-part-of-n-d-data

回答： Walter Roberson 2024-7-18，20:04

I made a class that has methods to return specific slices of an n-d array. I can use these methods as if they are properties, and subindexing works with one exception, I can't index with just a colon, I have to enclose it in quotes.

Here are examples where normal indexing works:

>> foobar = cfoobar(reshape(1:8,2,2,2))
foobar = 
cfoobar with no properties.
>> foobar.foo([2,1],[2,1])
ans =
4     2
3     1
>> foobar.bar(1:end,end)
ans =
7
8

Here is the example that doesn't work:

>> foobar.bar(:,end)
Input arguments to function include colon operator. To input the colon character, use ':' instead. 

Here is the example working with quotes:

>> foobar.bar(':',end)
ans =
     7
     8
>>

Here is the class:

classdef cfoobar
    properties (Access = private)
        foobar;
    end
    methods
        function obj = cfoobar(data)
            obj.foobar = data;
        end
        function data = foo(obj, varargin)
            data = obj.foobar(:,:,1);
            data = data(varargin{:});
        end
        function data = bar(obj, varargin)
            data = obj.foobar(:,:,2);
            data = data(varargin{:});           
        end
    end
end