tan - tangent function
#include <math.h> double tan(double x);
The tan() function computes the tangent of its argument x, measured in radians.An application wishing to check for error situations should set errno to 0 before calling tan(). If errno is non-zero on return, or the return value is NaN, an error has occurred.
The tan() function may lose accuracy when its argument is far from 0.0 .
Upon successful completion, tan() returns the tangent of x.If x is NaN, NaN is returned and errno may be set to [EDOM].
If x is ±Inf, either 0.0 is returned and errno is set to [EDOM], or NaN is returned and errno may be set to [EDOM].
If the correct value would cause overflow, ±HUGE_VAL is returned and errno is set to [ERANGE].
If the correct value would cause underflow, 0.0 is returned and errno may be set to [ERANGE].
The tan() function will fail if:
- [ERANGE]
- The value to be returned would cause overflow.
The tan() function may fail if:
- [EDOM]
- The value x is NaN or ±Inf.
- [ERANGE]
- The value to be returned would cause underflow.
No other errors will occur.
None.
None.
None.
atan(), isnan(), <math.h>.
Derived from Issue 1 of the SVID.