Amazon Redshift will no longer support the creation of new Python UDFs starting Patch 198. Existing Python UDFs will continue to function until June 30, 2026. For more information, see the [ blog post ](https://aws.amazon.com/blogs/big-data/amazon-redshift-python-user-defined-functions-will-reach-end-of-support-after-june-30-2026/). 

# ATAN2 function
<a name="r_ATAN2"></a>

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
<a name="r_ATAN2-synopsis"></a>

```
ATAN2(number1, number2)
```

## Arguments
<a name="r_ATAN2-arguments"></a>

 *number1*   
A `DOUBLE PRECISION` number. 

 *number2*   
A `DOUBLE PRECISION` number. 

## Return type
<a name="r_ATAN2-return-type"></a>

`DOUBLE PRECISION`

## Examples
<a name="r_ATAN2-examples"></a>

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 |
+-------------------+
```

To convert the arc tangent of `1/0` (which evaluates to 0) to the equivalent number of degrees, use the following example. 

```
SELECT (ATAN2(1,0) * 180/(SELECT PI())) AS degrees;

+---------+
| degrees |
+---------+
|      90 |
+---------+
```