# atan

> For the complete documentation index, see [llms.txt](https://docs.redpanda.com/llms.txt). Component-specific: [cloud-data-platform-full.txt](https://docs.redpanda.com/cloud-data-platform-full.txt)

---
title: atan
latest-operator-version: v26.2.4
latest-console-tag: v3.12.0
latest-connect-version: 4.113.1
latest-redpanda-tag: v26.2.4
docname: sql/sql-functions/math-functions/atan
page-component-name: cloud-data-platform
page-version: master
page-component-version: master
page-component-title: Cloud
page-relative-src-path: sql/sql-functions/math-functions/atan.adoc
page-edit-url: https://github.com/redpanda-data/cloud-docs/edit/main/modules/reference/pages/sql/sql-functions/math-functions/atan.adoc
description: The `atan()` function returns the inverse tangent (arctangent) of a specified argument, expressed in radians.
page-topic-type: reference
page-git-created-date: "2026-09-08"
page-git-modified-date: "2026-09-08"
---

<!-- Source: https://docs.redpanda.com/cloud-data-platform/reference/sql/sql-functions/math-functions/atan.md -->

The `atan()` function returns the inverse tangent (arctangent) of a specified argument, expressed in radians. See also [`atand()`](https://docs.redpanda.com/cloud-data-platform/reference/sql/sql-functions/math-functions/atand/) to return the result in degrees, and [`atan2()`](https://docs.redpanda.com/cloud-data-platform/reference/sql/sql-functions/math-functions/atan2/) to calculate the arctangent of a ratio of two arguments.

## [](#syntax)Syntax

```sql
ATAN(x)
```

## [](#arguments)Arguments

-   `x`: A number of type `real` or `double precision`.


## [](#return-type)Return type

Same as the input type (`real` or `double precision`).

## [](#examples)Examples

### [](#basic-usage)Basic usage

```sql
SELECT ATAN(1);
```

```sql
        atan
--------------------
 0.7853981633974483
(1 row)
```

### [](#zero-argument)Zero argument

```sql
SELECT ATAN(0);
```

```sql
 atan
------
    0
(1 row)
```