atan - Online Linux Manual PageSection : 3
Updated : 2023-02-05
Source : Linux man-pages 6.03

---

NAMEatan, atanf, atanl − arc tangent function

---

LIBRARYMath library (libm, −lm)

---

SYNOPSIS#include <math.h>double atan(double x); float atanf(float x); long double atanl(long double x);Feature Test Macro Requirements for glibc (see feature_test_macros(7)): atanf(), atanl(): _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

---

DESCRIPTIONThese functions calculate the principal value of the arc tangent of x; that is the value whose tangent is x.

---

RETURN VALUEOn success, these functions return the principal value of the arc tangent of x in radians; the return value is in the range [−pi/2, pi/2]. If x is a NaN, a NaN is returned. If x is +0 (−0), +0 (−0) is returned. If x is positive infinity (negative infinity), +pi/2 (−pi/2) is returned.

---

ERRORSNo errors occur.

---

ATTRIBUTESFor an explanation of the terms used in this section, see attributes(7). InterfaceAttributeValue atan(), atanf(), atanl() Thread safetyMT-Safe

---

STANDARDSC99, POSIX.1-2001, POSIX.1-2008. The variant returning double also conforms to SVr4, 4.3BSD.

---

SEE ALSOacos(3), asin(3), atan2(3), carg(3), catan(3), cos(3), sin(3), tan(3) 0

---

Johanes Gumabo

---

Data Size   :   8,424 byte
man-atanf.3Build   :   2024-12-05, 20:55   :  
Visitor Screen   :   x
Visitor Counter ( page / site )   :   2 / 227,887
Visitor ID   :     :  
Visitor IP   :   3.149.24.70   :  
Visitor Provider   :   AMAZON-02   :  
Provider Position ( lat x lon )   :   39.962500 x -83.006100   :   x
Provider Accuracy Radius ( km )   :   1000   :  
Provider City   :   Columbus   :  
Provider Province   :   Ohio ,   :   ,
Provider Country   :   United States   :  
Provider Continent   :   North America   :  
Visitor Recorder   :   Version   :  
Visitor Recorder   :   Library   :  
Online Linux Manual Page   :   Version   :   Online Linux Manual Page - Fedora.40 - march=x86-64 - mtune=generic - 24.12.05
Online Linux Manual Page   :   Library   :   lib_c - 24.10.03 - march=x86-64 - mtune=generic - Fedora.40
Online Linux Manual Page   :   Library   :   lib_m - 24.10.03 - march=x86-64 - mtune=generic - Fedora.40
Data Base   :   Version   :   Online Linux Manual Page Database - 24.04.13 - march=x86-64 - mtune=generic - fedora-38
Data Base   :   Library   :   lib_c - 23.02.07 - march=x86-64 - mtune=generic - fedora.36

---

Very long time ago, I have the best tutor, Wenzel Svojanovsky . If someone knows the email address of Wenzel Svojanovsky , please send an email to johanes_gumabo@yahoo.co.id .

---

If error, please print screen and send to johanes_gumabo@yahoo.co.id
Under development. Support me via PayPal.

---