# mustBeNonNan

Validate that value is not NaN

## Description

example

mustBeNonNan(value) throws an error if value is NaN. This function does not return a value.

mustBeNonNan calls the following function to determine if the input is not NaN:

Class support: All numeric classes, logical, and MATLAB® classes that overload isnan.

## Examples

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Use mustBeNonNan to validate that no array elements are NaN.

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

This function declares an input argument that must be a vector of doubles containing no NaN elements.

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
s = mbNonNan(values);
↑
Invalid input argument at position 1. Value must not be NaN.

## Input Arguments

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

• All MATLAB numeric classes and logical.

• MATLAB user-defined classes that implement isnan

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

## Tips

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

## Version History

Introduced in R2017a