# not

Logical NOT for symbolic expressions

## Syntax

``~A``
``not(A)``

## Description

example

````~A` represents the logical NOT. `~A` is true when `A` is false and false when `A` is true.```
````not(A)` is equivalent to `~A`.```

## Examples

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Create a logical condition by using `~`.

```syms x y cond = ~(x > y);```

Set the assumption represented by the condition using `assume`.

`assume(cond)`

Verify that the assumption is set.

`assumptions`
```ans = ~y < x```

Specify a range for `x` by creating a condition using the logical operators `~` and `&`.

```syms x range = abs(x) < 1 & ~(abs(x)<1/3);```

Return the conditions at `0` and `2/3` by substituting for `x` using `subs`. The `subs` function does not evaluate the conditions automatically.

```x1 = subs(range,x,0) x2 = subs(range,x,2/3)```
```x1 = 0 < 1 & ~0 < 1/3 x2 = 2/3 < 1 & ~2/3 < 1/3```

Evaluate the inequalities to logical `1` or `0` by using `isAlways`.

```isAlways(x1) isAlways(x2)```
```ans = logical 0 ans = logical 1```

## Input Arguments

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Input, specified as a number, vector, matrix, or array, or a symbolic number, variable, array, function, or expression.

## Version History

Introduced in R2012a