In Envision basic, there are many useful functions that comes handy. Especially when performing some quick mathematical operations, it saves us a few lines of code.

ABS and NEG are a couple of those kinds of functions that comes handy for math operations.

These functions are really easy to use and mostly don’t require any complex logic to use them.

## ABS Function

The ABS function is nothing but an absolute value function. It returns the positive numeric value of the

argument.

### Syntax

```
ABS(expr)
```

### Example

This will change *X.NUMBER* variable’s value to a positive 1 from a negative 1.

```
X.NUMBER = -1
X.NUMBER = ABS(X.NUMBER)
```

## NEG Function

The NEG function changes the value of the passes numeric value to the opposite sign value.

So, if the passes expression is of a positive value, it’ll change it to a negative value and return it.

If the passes expression is of a negative value, it’ll change it to a positive value and return it.

### Syntax

```
NEG(expr)
```

### Example

This will change *X.NUMBER* variable’s value to a positive 1 from a negative 1.

```
X.NUMBER = -1
X.NUMBER = NEG(X.NUMBER)
```

This will change *X.NUMBER* variable’s value to a negative 1 from a positive 1.

```
X.NUMBER = 1
X.NUMBER = NEG(X.NUMBER)
```

*absolute colleague examples functions studio*