A = 0./[-2 -1 0 1 2];
mustBeNonNan(A)

Error using mustBeNonNan (line 13)
Value must not be NaN.

Division of 0 by 0 is equal to NaN so the array value contains one element that is NaN, which causes an error.

This class restricts the value of Prop1 to nonNaN values.

classdef MyClass
   properties
      Prop1 {mustBeNonNan}
   end
end

Create an object and assign a value to Prop1.

obj = MyClass;
obj.Prop1 = 0./[-2 -1 0 1 2];

Error setting property 'Prop1' of class 'MyClass':
Value must not be NaN.

When you assign a value to the property, MATLAB calls mustBeNonNan with the value being assigned to the property. mustBeNonNan issues an error because division of 0 by 0 is NaN.

function s = mbNonNan(x)
    arguments
        x (1,:) double {mustBeNonNan}
    end
    n = length(x);
    m = sum(x)/n;
    s = sqrt(sum((x-m).^2/n));
end

Calling the function with an input that does not meet the requirement of mustBeNonNan results in an error.

values = [12.7, 45.4, 98.9, NaN, 53.1];
s = mbNonNan(values);

Error using mbNonNan
Invalid input argument at position 1. Value must not be NaN.