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Validate that value is less than another value



mustBeLessThan(value,c) throws an error if any elements in value are greater than or equal to the scalar c. This function does not return a value.

mustBeLessThan calls these functions to determine if value is less than c:

Class support: All numeric classes, logical, and MATLAB® classes that overload the functions called by mustBeLessThan.

This function ignores empty values in the first input argument. Therefore, no error is thrown when the property or function argument value is empty.


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Use mustBeLessThan to validate that the values in the first input are less than the value of the second input.

mustBeLessThan([2 3 4],2)
Value must be less than 2.

Restrict property values to be less than a specified value.

This class constrains the value of Prop1 to be less than 2.

classdef MyClass
      Prop1 {mustBeLessThan(Prop1,2)}

Create an object and assign a value to its property.

obj = MyClass;
obj.Prop1 = 2;
Error setting property 'Prop1' of class 'MyClass'. Value must be less than 2.

When you assign a value to the property, MATLAB calls mustBeLessThan with the value being assigned to the property. mustBeLessThan issues an error because the value 2 is not less than 2.

This function restricts the input argument to be values that are less than 5.

function r = mbLessThan(x)
        x {mustBeLessThan(x,5)}
    r = x + 5;

Calling the function with a vector that contains values that are greater than or equal to 5 does not meet the requirements defined with mustBeLessThan and results in an error.

x = [1.27, 4.54, 3.9, 5.0, .531];
r = mbLessThan(x);
Error using mbLessThan
 r = mbLessThan(x);
Invalid input argument at position 1. Value must be less than 5.

Input Arguments

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Value to validate, specified as a scalar or an array of one of the following:

When using mustBeLessThan as a property validator, this argument must be the property name, specified without quotation marks.

Constant value that the value argument must be less than, specified as a scalar of one of the following:


  • mustBeLessThan is designed to be used for property and function argument validation.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced in R2017a