Contents

Index

• Getting Started

• User Guide

• Functions

• Desktop Tools and Development Environment

• Data Import and Export

• Mathematics

• Arrays and Matrices

• Linear Algebra

• Elementary Math

• Trigonometric

• Exponential

• Complex

• Rounding and Remainder

• Discrete Math

• Polynomials

• Interpolation and Computational Geometry

• Cartesian Coordinate System Conversion

• Nonlinear Numerical Methods

• Specialized Math

• Sparse Matrices

• Math Constants

• Data Analysis

• Programming and Data Types

• Object-Oriented Programming

• Graphics

• 3-D Visualization

• GUI Development

• External Interfaces

• Examples

• Release Notes

Learn more about MATLAB

atan - Inverse tangent; result in radians

Syntax

Y = atan(X)

Description

Y = atan(X) returns the inverse tangent (arctangent) for each element of X. For real elements of X, atan(X) is in the range .

The atan function operates element-wise on arrays. The function's domains and ranges include complex values. All angles are in radians.

Examples

Graph the inverse tangent function over the domain .

x = -20:0.01:20; 
plot(x,atan(x)), grid on

Definition

The inverse tangent can be defined as

Algorithm

atan uses FDLIBM, which was developed at SunSoft, a Sun Microsystems business, by Kwok C. Ng, and others. For information about FDLIBM, see http://www.netlib.org.