mustBeLessThanOrEqual

Validate that value is less than or equal to another value

Syntax

mustBeLessThanOrEqual(value,c)

Description

mustBeLessThanOrEqual(value,c) throws an error if any elements in value are greater than c. This function does not return a value.

mustBeLessThanOrEqual calls the le function to determine if value is less than or equal to c. (since R2026a)

Class support: All numeric classes, logical, and MATLAB^® classes that implement le.

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 or Equal to Second

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

mustBeLessThanOrEqual([3 4 5],2)

Value must be less than or equal to 2.

Restrict Property Values

Restrict property values to be less than or equal to a specified value.

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

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

Create an object and assign a value to its property.

obj = MyClass;
obj.Prop1 = 3;

Error setting property 'Prop1' of class 'MyClass'. Value must be less than or equal to 2.

When you assign a value to the property, MATLAB calls mustBeLessThanOrEqual with the value being assigned to the property. mustBeLessThanOrEqual issues an error because the value 3 is not less than or equal to 2.

Restrict Function Argument Values

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

function r = mbLessThanOrEqual(x)
    arguments
        x {mustBeLessThanOrEqual(x,5)}
    end
    r = x + 5;
end

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

x = [1.27, 4.54, 3.9, 5.1, .531];
r = mbLessThanOrEqual(x);

Error using mbLessThanOrEqual (line 3)
 r = mbLessThanOrEqual(x);
                       ^
Invalid argument at position 1. Value must be less than or equal to 5.

Input Arguments

value — Value to validate

scalar | array

Value to validate, specified as a scalar or an array of one of these types:

• logical, char, string, or numeric class

• MATLAB classes that implement le

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | logical | char | string | categorical | datetime | duration | table | timetable
Complex Number Support: Yes

c — Constant value that the value argument must be less than or equal to

scalar | array

Constant value that the value argument must be less than or equal to, specified as a scalar or an array of one of these types:

• logical, char, string, or numeric class

• MATLAB classes that implement le

Inputs c and value must have compatible sizes (for example, value is an M-by-N matrix and c is a scalar or 1-by-N row vector). For more information, see Compatible Array Sizes for Basic Operations.

Before R2026a: c must be scalar.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | logical | char | string | categorical | datetime | duration | table | timetable
Complex Number Support: Yes

Tips

• mustBeLessThanOrEqual 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 Code Generation
Generate CUDA® code for NVIDIA® GPUs using GPU Coder™.

GPU Arrays

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

The mustBeLessThanOrEqual 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™.

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

Version History

Introduced in R2017a

R2026a: mustBeLessThanOrEqual no longer restricts inputs to be real, numeric, or logical

The mustBeLessThanOrEqual function no longer calls the isreal, isnumeric, and islogical functions to validate input. As a result, mustBeLessThanOrEqual accepts any data type supported by the underlying comparison operator le (or <=), such as character vectors, strings, and date and time types.

For example, the compareValues function restricts input argument values using the mustBeLessThanOrEqual validation function.

function obj = compareValues(startValue,endValue)
    arguments
        startValue
        endValue {mustBeLessThanOrEqual(startValue,endValue)}
    end
end

The compareValues function now accepts data of type datetime as input.

A = datetime("yesterday");
B = datetime("today");
compareValues(A,B)

In previous releases, calling compareValues with datetime inputs returned this error:

Error using compareValues (line 4)
Inputs to function 'mustBeLessThanOrEqual' must be numeric or logical.

To preserve the behavior of previous releases, explicitly use mustBeReal and mustBeNumericOrLogical in your validation checks. For example, this code preserves the previous behavior of mustBeLessThanOrEqual in the compareValues function definition.

function obj = compareValues(startValue,endValue)
    arguments
        startValue {mustBeReal,mustBeNumericOrLogical}
        endValue {mustBeReal,mustBeNumericOrLogical, ...
                  mustBeLessThanOrEqual(startValue,endValue)}
    end
end

R2026a: Compare two inputs with compatible array sizes

The mustBeLessThanOrEqual function now supports implicit expansion when comparing two inputs with compatible array sizes, similar to the implicit expansion behavior in arithmetic operations.

For example, the compareValues function restricts input argument values using the mustBeLessThanOrEqual validation function.

function obj = compareValues(startValue,endValue)
    arguments
        startValue
        endValue {mustBeLessThanOrEqual(startValue,endValue)}
    end
end

The compareValues function now accepts inputs with compatible array sizes.

compareValues([-2; -1],[3 2 1])

In previous releases, calling compareValues on 2-by-1 and 1-by-3 input arrays returned this error:

Error using compareValues (line 4)
Second input to function 'mustBeLessThanOrEqual' must be a scalar.