GNU/Linux |
CentOS 5.5 |
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atanl(3) |
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atan, atanf, atanl − arc tangent function
#include <math.h>
double
atan(double x);
float atanf(float x);
long double atanl( long double x);
Link with −lm.
The atan() function calculates the arc tangent of x; that is the value whose tangent is x.
The atan() function returns the arc tangent in radians and the value is mathematically defined to be between −PI/2 and PI/2 (inclusive).
SVr4, POSIX.1-2001, 4.3BSD, C89. The float and long double variants are C99 requirements.
acos(3), asin(3), atan2(3), carg(3), catan(3), cos(3), sin(3), tan(3)
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atanl(3) | ![]() |