> For the complete documentation index, see [llms.txt](https://nelson-9.gitbook.io/nelson/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://nelson-9.gitbook.io/nelson/markdown/en/validators/mustbenonzero.md).

# mustBeNonZero

Checks that value is not zero.

## 📝 Syntax

* mustBeNonZero(var)
* mustBeNonZero(var, argPosition)
* C++: void mustBeNonZero(const ArrayOfVector& args, int argPosition)

## 📥 Input argument

* var - a variable: all supported types and classes that implement eq, isnumeric and islogical methods.
* argPosition - a positive integer value: Position of input argument.

## 📄 Description

mustBeNonZero checks that value is not zero or raise an error.

## 💡 Example

```matlab
mustBeNonZero(1)
mustBeNonZero([])
mustBeNonZero(NaN)
mustBeNonZero(0)

```

## 🔗 See also

[isempty](/nelson/markdown/en/types/isempty.md), [eq](/nelson/markdown/en/operators/eq.md).

## 🕔 History

| Version | 📄 Description  |
| ------- | --------------- |
| 1.0.0   | initial version |


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