Is it possible to customize the isequal function for own classes, i.e. to define when two handle-class objects are considered as equal by content? I would like to explain my question in more detail below:
Please consider the following simple data class
classdef Data < handle properties value end methods function self = Data(value) self.value = value; end endend
Following MathWorks — Equality of Handle Objects one can check if two objects of the Data class point to the same reference using the == operator. In contrast, one can test if two objects are equal by content using the Matlab built-in isequal function.
This works fine. However, I now would like to override the isequal behaviour for my class. For example, I would like to define that two Data objects are equal by content if the values of their property value are equal within an absolute tolerance of 1e-8. How could I achieve that?
Note:
Im aware of the possibility of overriding the eq-method of the Data class:
classdef Data < handle properties value end methods function self = Data(value) self.value = value; end function is_eq = eq(self, other) if not(strcmp(class(self), class(other))) is_eq = false; return end is_eq = abs(self.value - other.value) < 1e-8; end endend
Therewith I can test the equality of two objects by content using the == operator. However, from my point of view this is problematic because: i) It is inconsistent with the initial/previous behavior because the == operator no longer compares two objects by reference but by content instead. And, ii) in addition, I lose the possiblity to check if two objects have the same reference.
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