# not() function

The not() function returns the logical
inverse of the normal outcome of true and false generated by a logical
expression.

## Syntax

```
not(logical.exp)
```

## Parameter(s)

| logical.exp | Expression to test. |
| --- | --- |

## Description

If the expression evaluates
to 0, then 1 is returned. If the expression evaluates to any nonzero
value, 0 is returned.

## Example(s)

If `response` is
not numeric, this prints `"not numeric"`.

```
if not(num(response)) then print "not numeric"
```

## See also

- [= assignment operator](https://d3codex.com/pickbasic-flashbasic/equals-assignment-operator/)
- [Boolean evaluation](https://d3codex.com/pickbasic-flashbasic/boolean-evaluation/)
- [BASIC functions](https://d3codex.com/pickbasic-flashbasic/basic-functions/)
- [if statement](https://d3codex.com/pickbasic-flashbasic/if-statement/)
- [ifr statement](https://d3codex.com/pickbasic-flashbasic/ifr-statement/)
- [mod() function](https://d3codex.com/pickbasic-flashbasic/mod-function/)
- [ne relational operator](https://d3codex.com/pickbasic-flashbasic/ne-relational-operator/)
- [null statement](https://d3codex.com/pickbasic-flashbasic/null-statement/)
- [rem() function](https://d3codex.com/pickbasic-flashbasic/rem-function/)
- [Statements and functions](https://d3codex.com/pickbasic-flashbasic/statements-and-functions/)
- [then clause](https://d3codex.com/pickbasic-flashbasic/then-clause/)

---
Source: https://d3codex.com/pickbasic-flashbasic/not-function/ - part of the D3Codex reference.