# false

Logical 0 (false)

## Syntax

``false``
``F = false(n)``
``F = false(sz)``
``F = false(sz1,...,szN)``
``F = false(___,'like',p)``

## Description

example

``false` is shorthand for the logical value `0`.`

example

````F = false(n)` is an `n`-by-`n` array of logical zeros.```

example

````F = false(sz)` is an array of logical zeros where the size vector, `sz`, defines `size(F)`. For example, ```false([2 3])``` returns a 2-by-3 array of logical zeros.```

example

````F = false(sz1,...,szN)` is a `sz1`-by-`...`-by-`szN` array of logical zeros where `sz1,...,szN` indicates the size of each dimension. For example, `false(2,3)` returns a 2-by-3 array of logical zeros.```

example

````F = false(___,'like',p)` returns an array of logical zeros of the same sparsity as the logical variable `p` using any of the previous size syntaxes.```

## Examples

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Use `false` to generate a 3-by-3 square matrix of logical zeros.

`A = false(3)`
```A = 3x3 logical array 0 0 0 0 0 0 0 0 0 ```
`class(A)`
```ans = 'logical' ```

The result is of class `logical`.

Use `false` to generate a 3-by-2-by-2 array of logical zeros.

`false(3,2,2)`
```ans = 3x2x2 logical array ans(:,:,1) = 0 0 0 0 0 0 ans(:,:,2) = 0 0 0 0 0 0 ```

Alternatively, use a size vector to specify the size of the matrix.

`false([3 2 2])`
```ans = 3x2x2 logical array ans(:,:,1) = 0 0 0 0 0 0 ans(:,:,2) = 0 0 0 0 0 0 ```

Note that specifying multiple vector inputs returns an error.

`false` along with `true` can be used to execute logic statements.

Test the logical statement

` ~(A and B) = (~A) or (~B)`

for `A = false` and `B = true`.

`~(false & true) == (~false) | (~true)`
```ans = logical 1 ```

The result is logical 1 (true), since the logical statements on both sides of the equation are equivalent. This logical statement is an instance of De Morgan's Law.

Generate a logical array of the same data type and sparsity as the selected array.

```A = logical(sparse(5,3)); whos A```
``` Name Size Bytes Class Attributes A 5x3 41 logical sparse ```
```F = false(4,'like',A); whos F```
``` Name Size Bytes Class Attributes F 4x4 49 logical sparse ```

The output array `F` has the same `sparse` attribute as the specified array `A`.

## Input Arguments

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Size of square matrix, specified as an integer. `n` sets the output array size to `n`-by-`n`. For example, `false(3)` returns a 3-by-3 array of logical zeros.

• If `n` is `0`, then `F` is an empty matrix.

• If `n` is negative, then it is treated as `0`.

Data Types: `int8` | `int16` | `int32` | `int64` | `uint8` | `uint16` | `uint32` | `uint64`

Size vector, specified as a row vector of integers. For example, ```false([2 3)]``` returns a 2-by-3 array of logical zeros.

• If the size of any dimension is `0`, then `F` is an empty array.

• If the size of any dimension is negative, then it is treated as `0`.

• If any trailing dimensions greater than `2` have a size of `1`, then the output, `F`, does not include those dimensions.

Data Types: `int8` | `int16` | `int32` | `int64` | `uint8` | `uint16` | `uint32` | `uint64`

Size inputs, specified by a comma-separated list of integers. For example, `false(2,3)` returns a 2-by-3 array of logical zeros.

• If the size of any dimension is `0`, then `F` is an empty array.

• If the size of any dimension is negative, then it is treated as `0`.

• If any trailing dimensions greater than `2` have a size of `1`, then the output, `F`, does not include those dimensions.

Data Types: `int8` | `int16` | `int32` | `int64` | `uint8` | `uint16` | `uint32` | `uint64`

Prototype, specified as a logical variable.

Data Types: `single` | `double` | `int8` | `int16` | `int32` | `int64` | `uint8` | `uint16` | `uint32` | `uint64`

## Output Arguments

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Output of logical zeros, returned as a scalar, vector, matrix, or N-D array.

Data Types: `logical`

## Tips

• `false(n)` is much faster and more memory efficient than `logical(zeros(n))`.

## Version History

Introduced before R2006a