Full_Name: Peter Fortini
Version: 2.0.1
OS: Windows 2000
Submission from: (NULL) (65.246.187.164)
When the imaginary part of the argument is very large, the complex tangent
function returns 0+NaNi. For example, tan(1+1000i)=0+NaNi; it should be 0+1i
Easy to fix in complex.c, as the original NaN came from division of sinh and
cosh that had reached machine infinity.
static void z_tan(Rcomplex *r, Rcomplex *z)
{
double x2, y2, den;
x2 = 2.0 * z->r;
y2 = 2.0 * z->i;
den = cos(x2) + cosh(y2);
r->r = sin(x2)/den;
/* any limit above about log(DBL_EPSILON) will do */
if (fabs(r->i) < 40.0)
r->i = sinh(y2)/den;
else
r->i = 1.0;
}
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