| Pré. | Proc. |
tandg
Circular tangent of argument in degrees.SYNOPSIS:
double x, y, tandg();
y = tandg(x);
DESCRIPTION:
Returns the circular tangent of the argument x in degrees.
Range reduction is modulo pi/4. A rational function:
x + x**3 P(x**2)/Q(x**2)
is employed in the basic interval [0, pi/4].
ACCURACY:
Relative error:
arithmetic domain # trials peak rms
DEC 0,10 8000 3.4e-17 1.2e-17
IEEE 0,10 30000 3.2e-16 8.4e-17
ERROR MESSAGES:
message condition value returned
total loss x > 8.0e14 (DEC) 0.0
x > 1.0e14 (IEEE)
singularity x = 180 k + 90 MAXNUM