apparentEccentricity function
Apparent eccentricity from true orbital elements.
Implementation
double apparentEccentricity(double e, double i, double w) {
final ci = math.cos(i);
final sW = math.sin(w), cW = math.cos(w);
final aa = (1 - e * e * cW * cW) * ci * ci;
final b = e * e * sW * cW * ci;
final cc = 1 - e * e * sW * sW;
final d = aa - cc;
final sD = math.sqrt(d * d + 4 * b * b);
return math.sqrt(2 * sD / (aa + cc + sD));
}