# ATAN2 function
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ATAN2 is a trigonometric function that returns the arc tangent of one number divided by another number. The return value is in radians and is between `PI/2` and `-PI/2`. 

## Syntax
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```
ATAN2(number1, number2)
```

## Arguments
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 *number1*   
A `DOUBLE PRECISION` number. 

 *number2*   
A `DOUBLE PRECISION` number. 

## Return type
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`DOUBLE PRECISION`

## Examples
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To return the arc tangent of `2/2` and multiply it by 4, use the following example. 

```
SELECT ATAN2(2,2) * 4 AS PI;

+-------------------+
|        pi         |
+-------------------+
| 3.141592653589793 |
+-------------------+
```