char *
v3fmt(V3 v)
{
char *p;
/* get a buffer */
p = v3buf[nxtv3buf++];
nxtv3buf %= NV3BUF;
if (v3GetType(v) == CARTESIAN) {
(void)sprintf(p, "%22.15e %22.15e %22.15e",
v3GetX(v),
v3GetY(v),
v3GetZ(v));
} else {
(void)sprintf(p, "%22.15e %22.15e %22.15e",
v3GetR(v),
v3GetAlpha(v),
v3GetDelta(v));
}
return(p);
}
double
v3alpha(V3 v)
{
double alpha;
if (v3GetType(v) == CARTESIAN) {
v = v3c2s(v);
}
alpha = v3GetAlpha(v);
if (v3GetR(v) < 0.0) {
alpha += M_PI;
}
if (alpha < 0.0) {
alpha += ceil(alpha / (-2 * M_PI)) * (2 * M_PI);
}
if (alpha >= (2 * M_PI)) {
alpha -= floor(alpha / (2 * M_PI)) * (2 * M_PI);
}
return(alpha);
}