## table of contents

ATAN(3clc) | OpenCL Manual | ATAN(3clc) |

# NAME¶

atan,_atan2,_atanh,_atanpi,_atan2pi - Tangent functions.

# ¶

**gentype atan(gentype ***y_over_x***);**

**gentype atan2(gentype ***y***,
gentype ***x***);**

**gentype atanh(gentype ****);**

**gentype atanpi(gentype ***x***);**

**gentype atan2pi(gentype ***y***,
gentype ***x***);**

# DESCRIPTION¶

**atan** is the arc tangent function.

**atan2** is the arc tangent of *y* / *x*.

**atanh** is the hyperbolic arc tangent function.

**atanpi** computes **atan** (*x*) / π.

**atan2pi** computes **atan2** (*y*, *x*) /
π.

# NOTES¶

The vector versions of the math functions operate component-wise. The description is per-component.

The built-in math functions are not affected by the prevailing rounding mode in the calling environment, and always return the same value as they would if called with the round to nearest even rounding mode.

The built-in math functions take scalar or vector arguments. For any specific use of these function, the actual type has to be the same for all arguments and the return type unless otherwise specified.

The generic type name **gentype** is used to indicate that the
function can take **float**, **float2**, **float3**, **float4**,
**float8**, **float16**, **double**, **double2**,
**double3**, **double4**, **double8**, or **double16** as the
type for the arguments.

If extended with **cl_khr_fp16**(3clc), generic type name
**gentype** may indicate **half** and **half{2|3|4|8|16}** as
arguments and return values.

The generic type name **gentypef** is used to indicate that the
function can take **float**, **float2**, **float3**, **float4**,
**float8**, or **float16** as the type for the arguments.

The generic type name **gentyped** is used to indicate that the
function can take **double**, **double2**, **double3**,
**double4**, **double8**, or **double16** as the type for the
arguments.

# SPECIFICATION¶

**OpenCL Specification**[1]

# SEE ALSO¶

**mathFunctions**(3clc)

# AUTHORS¶

**The Khronos Group**

# COPYRIGHT¶

Copyright © 2007-2011 The Khronos Group Inc.

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and/or associated documentation files (the
"Materials"), to deal in the Materials without restriction,
including without limitation the rights to use, copy, modify, merge,
publish, distribute, sublicense, and/or sell copies of the Materials, and to
permit persons to whom the Materials are furnished to do so, subject to the
condition that this copyright notice and permission notice shall be included
in all copies or substantial portions of the Materials.

# NOTES¶

- 1.
- OpenCL Specification

01/14/2021 | The Khronos Group |