# isempty

Determine whether array is empty

## Syntax

``TF = isempty(A)``

## Description

example

````TF = isempty(A)` returns logical `1` (`true`) if `A` is empty, and logical `0` (`false`) otherwise. An empty array, table, or timetable has at least one dimension with length 0, such as 0-by-0 or 0-by-5.```

## Examples

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Create a 3-D array with one dimension length equal to zero, and determine if it is empty.

```A = zeros(0,2,2); TF = isempty(A)```
```TF = logical 1 ```

Compare empty arrays to arrays containing missing values.

In MATLAB®, an empty array has at least one dimension length equal to zero. An array containing missing values, such as `NaN` or `<undefined>`, is not necessarily empty.

Create a categorical vector with missing values.

`cat1 = categorical([missing missing])`
```cat1 = 1x2 categorical <undefined> <undefined> ```

Since `cat1` does not have a dimension of length zero, it is not empty.

`TF1 = isempty(cat1)`
```TF1 = logical 0 ```

Create a 0-by-0 categorical array and test if it is empty.

```cat2 = categorical([]); TF2 = isempty(cat2)```
```TF2 = logical 1 ```

Compare empty string arrays and strings with no characters.

Create a string vector whose elements are strings with no characters. `str1` is nonempty since none of its dimensions have length zero.

`str1 = strings(1,3)`
```str1 = 1x3 string "" "" "" ```
`TF1 = isempty(str1)`
```TF1 = logical 0 ```

Create a 0-by-3 string array and test if it is empty.

```str2 = strings(0,3); TF2 = isempty(str2)```
```TF2 = logical 1 ```

## Input Arguments

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Input array or table, specified as a scalar, vector, matrix, multidimensional array, table, or timetable.

## Tips

• To determine whether a string array has empty strings (string elements with zero characters), use the `==` operator. For example, if `str` is a string containing zero characters, then ```str == ""``` returns logical `1` (`true`). For more information on testing empty strings, see Test for Empty Strings and Missing Values. For information on string comparison, see Compare Text.

• To test for missing values in an array, use the `ismissing` function.

## Version History

Introduced before R2006a