NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | ATTRIBUTES | SEE ALSO
cc [ flag ... ] file ... -lm [ library ... ] #include <math.h>double atan(double x);
Upon successful completion, atan() returns the arc tangent of x in the range [-pi/2,pi/2] radians.
If x is NaN, NaN is returned.
If x is ±Inf, ±pi/2 is returned.
No errors will occur.
See attributes(5) for descriptions of the following attributes:
ATTRIBUTE TYPE | ATTRIBUTE VALUE |
---|---|
MT-Level | MT-Safe |
NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | ATTRIBUTES | SEE ALSO