struct xpr
cxabs (struct cxpr z)
{
struct xpr x;
int ea, eb;
if (xprcmp (&z.re, &xZero) == 0 && xprcmp (&z.im, &xZero) == 0)
return xZero;
else
{
ea = (z.re.nmm[0] &= xM_exp) - xBias;
eb = (z.im.nmm[0] &= xM_exp) - xBias;
if (ea > eb + XBOUND)
return z.re;
else if (eb > ea + XBOUND)
return z.im;
else
{
z.re.nmm[0] -= eb;
z.im.nmm[0] = xBias;
x = xsqrt (xadd (xmul (z.re, z.re), xmul (z.im, z.im), 0));
x.nmm[0] += eb;
return x;
}
}
}
int
cxrec (struct cxpr z, struct cxpr *w)
{
struct xpr x;
int sa, sb, ea, eb;
if (xprcmp (&z.re, &xZero) == 0 && xprcmp (&z.im, &xZero) == 0)
return 0;
else
{
sa = z.re.nmm[0] & xM_sgn;
sb = z.im.nmm[0] & xM_sgn;
ea = (z.re.nmm[0] &= xM_exp) - xBias;
eb = (z.im.nmm[0] &= xM_exp) - xBias;
if (ea > eb + XBOUND)
x = z.re;
else if (eb > ea + XBOUND)
x = z.im;
else
{
z.re.nmm[0] -= eb;
z.im.nmm[0] = xBias;
x = xsqrt (xadd (xmul (z.re, z.re), xmul (z.im, z.im), 0));
x.nmm[0] += eb;
z.re.nmm[0] += eb;
z.im.nmm[0] += eb;
}
w->re = xdiv (xdiv (z.re, x), x);
w->im = xdiv (xdiv (z.im, x), x);
w->re.nmm[0] |= sa;
w->im.nmm[0] |= xM_sgn ^ sb;
return 1;
}
}
main ()
{
global_x = 100.0;
printf ("", &global_x, &global_y); /* Frighten the optimizer. */
global_y = xsqrt (global_x / 2.0); /* Compensate for the "x += x;" in xsqrt(). */
if (global_y != 10.0)
abort ();
exit (0);
}
Angle
dist(Angle ra1, Angle dec1, Angle ra2, Angle dec2)
{
double a;
a = sin(dec1) * sin(dec2) +
cos(dec1) * cos(dec2) *
cos(ra1 - ra2);
a = atan2(xsqrt(1 - a*a), a);
if(a < 0)
a = -a;
return a;
}
int
main (void)
{
struct xpr z, w, f, u;
printf (" Test of Sqrt Function\n");
z = xZero;
w = atox ("0.2");
u = atox ("4.01");
for (; xprcmp (&z, &u) < 0; z = xadd (z, w, 0))
{
/* compute extended precision square root */
f = xsqrt (z);
printf (" %8.4f ", xtodbl (z));
xprxpr (f, decd);
putchar ('\n');
}
return 0;
}