Calculating coordinates given a bearing and a distance

Question

I am having problems implementing the function described here here.

This is my Java implementation:

private static double[] pointRadialDistance(doubl         


        

Answer 1

Thanks for your python code I tried setting it up in my use case where I'm trying to find the lat lon of a point in between two others at a set distance from the first point so it's quite similare to your code appart that my bearing is dynamically calculated

startpoint(lat1) lon1/lat1 = 55.625541,-21.142463

end point (lat2) lon2/lat2 = 55.625792,-22.142248

my result should be a point in between these two at lon3/lat3 unfortunetly I get lon3/lat3 = 0.0267695450609,0.0223553243666

I thought this might be a difference in lat lon but no when I add or sub it it's not good

any advice would be really great Thanks

here's my implementation

distance = 0.001 epsilon = 0.000001

calculating bearing dynamically

y = math.sin(distance) * math.cos(lat2);
x = math.cos(lat1)*math.sin(lat2) - math.sin(lat1)*math.cos(lat2)*math.cos(distance);
bearing = math.atan2(y, x)

calculating lat3 lon3 dynamically

rlat1 = (lat1 * 180) / math.pi
rlon1 = (lon1 * 180) / math.pi
rbearing = (bearing * 180) / math.pi
rdistance = distance / R # normalize linear distance to radian angle

rlat = math.asin( math.sin(rlat1) * math.cos(rdistance) + math.cos(rlat1) * math.sin(rdistance) * math.cos(rbearing) )
if math.cos(rlat) == 0 or abs(math.cos(rlat)) < epsilon: # Endpoint a pole
      rlon=rlon1
else:
    rlon = ( (rlon1 + math.asin( math.sin(rbearing)* math.sin(rdistance) / math.cos(rlat) ) + math.pi ) % (2*math.pi) ) - math.pi

lat3 = (rlat * math.pi)/ 180
lon3 = (rlon * math.pi)/ 180