static int Main(string[] args)
{
if (args.Length != 2)
{
Console.WriteLine("{0}", UsageText);
return(1);
}
const double MAX_HEIGHT_METERS = 100000.0;
// Force use of "." for the decimal mark, regardless of local culture settings.
Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;
double latitude = double.Parse(args[0]);
if (!double.IsFinite(latitude) || latitude < -90.0 || latitude > +90.0)
{
Console.WriteLine($"ERROR: Invalid latitude '{args[0]}'. Must be a number between -90 and +90.");
return(1);
}
double height = double.Parse(args[1]);
if (!double.IsFinite(height) || height < 0.0 || height > MAX_HEIGHT_METERS)
{
Console.WriteLine($"ERROR: Invalid height '{args[1]}'. Must be a number between 0 and {MAX_HEIGHT_METERS:F0}.");
return(1);
}
double gravity = Astronomy.ObserverGravity(latitude, height);
Console.WriteLine($"latitude = {latitude,8:F4}, height = {height,6:F0}, gravity = {gravity,8:F6}");
return(0);
}