mustBeLessThan

Validate that value is less than another value

Syntax

mustBeLessThan(value,c)

Description

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:

• lt

• isreal

• isnumeric

• islogical

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.

Examples

Validate First Input Less Than Second

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

Restrict property values to be less than a specified value.

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

classdef MyClass
   properties
      Prop1 {mustBeLessThan(Prop1,2)}
   end
end

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.

Restrict Function Argument Values

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

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

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 (line 3)
 r = mbLessThan(x);
                ^
Invalid argument at position 1. Value must be less than 5.

Input Arguments

value — Value to validate

scalar | array

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

• logical, char, string, or numeric class

• MATLAB classes that implement lt, isscalar, isreal, and either isnumeric or islogical

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

c — Constant value that the value argument must be less than

scalar

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

• Any numeric class

• Logical class

• MATLAB classes that implement lt, isscalar, isreal, and either isnumeric or islogical

Tips

• 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™.

GPU Arrays

Accelerate code by running on a graphics processing unit (GPU) using Parallel Computing Toolbox™.

The mustBeLessThan function fully supports GPU arrays. To run the function on a GPU, specify the input data as a gpuArray (Parallel Computing Toolbox). For more information, see Run MATLAB Functions on a GPU (Parallel Computing Toolbox).

Distributed Arrays

Partition large arrays across the combined memory of your cluster using Parallel Computing Toolbox™.

This function fully supports distributed arrays. For more information, see Run MATLAB Functions with Distributed Arrays (Parallel Computing Toolbox).

Version History

Introduced in R2017a