mustBeNumeric

Validate that value is numeric

Syntax

mustBeNumeric(value)

Description

mustBeNumeric(value) throws an error if value contains nonnumeric. This function does not return a value.

mustBeNumeric calls the following function to determine if the input is numeric:

• isnumeric

This function ignores input arguments that are empty values. Therefore, no error is thrown when the property or function argument value is empty.

Examples

Validate That Input Is Numeric

Validate that the result of an operation is numeric.

mustBeNumeric(5 < 10)

Value must be numeric.

The relational operator for less than returns a logical value.

Restrict Property Values

This class restricts the value of Prop1 to numeric values.

classdef MyClass
   properties
      Prop1 {mustBeNumeric}
   end
end

Create an object and assign a value to its property.

obj = MyClass;
obj.Prop1 = isprime(29);

Error setting property 'Prop1' of class 'MyClass'. Value must be numeric.

When you assign a value to the property, MATLAB^® calls mustBeNumeric with the value being assigned to the property. mustBeNumeric issues an error because the value assigned to Prop1 is a logical.

Restrict Function Values

This function restricts the input argument to a numeric vector.

function r = mbNumeric(x)
    arguments
        x (1,:) {mustBeNumeric}
    end
    p = [3 2 1];
    r = polyval(p,x);
end

Calling this function with a character vector results in an error being thrown by mustBeNumeric.

x = '4 3 2';
r = mbNumeric(x);

Error using mbNumeric (line 3)
 r = mbNumeric(x);
               ^
Invalid argument at position 1. Value must be numeric.

Input Arguments

value — Value to validate

scalar | array

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

• Any MATLAB numeric class

• MATLAB classes that derive from a MATLAB numeric type or that overload isnumeric

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64
Complex Number Support: Yes

Tips

• mustBeNumeric 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 mustBeNumeric 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