GPS code translator

[JonBMN]

I understand you can use the Haversine formula or Vincenty formulae but I don't even know where to begin to understand these formulas and plug in my values.

Heres what I've done incase anyone wants to see:

$Miles = sin($IniLatitude - $Latitude/2) + cos($IniLatitude - $Latitude)*sin($IniLongitude - $Longitude/2)
$Hours = $TimeElapsed/3600000
Abs($MPH = $Miles / $Hours)
ConsoleWrite($MPH & @CR)

Edited September 14, 2012 by JonBMN

[AlainB]

I don't know wy you are still trying to work on the speed! As I told you before It is already given to you by the GPS.

For the distance between 2 coordinates, have a look again at my thread. I just posted the function for that.

Alain

[JonBMN]

Yes the GPS gives you the Knots which you have to convert to Miles, but it does not give you the MPH; this is what I was trying to find; and the function above gives it to you.

For your distance between the 2 coordinates its finding the straight shot. This is not what you want in a gps because you would have the true mph and coordinates which you need to have because roads are not straight shots to places; they turn and loop and go everywhere but not straight there.

[BrewManNH]

Knots is a measure of speed, not a measure of distance, so all you have to do is convert Knots to MPH, so for example $Knots = 10, $MPH = $Knots * 1.15078. You're trying to calculate distance travelled, and not the distance between two points. If you're looking to create a navigation GPS using actual routes to travel and distance based on that, good luck because that's a whole new world to explore what with road mapping and acurate maps.

[AlainB]

The speed that gives any GPS is very accurate as long as it is more than maybe 5 Km/h.

By the way, the straight line and bearing is what you would like to have if you are flying or sailing or walking in the bush or for me when I am in another country for the distance and bearing of my hotel or any other point that I am looking for.

Straight line and bearing is also very handy to find your car in a huge parking. There are some small GPS that do just that.

Since GPS are updating every second, you can compute the distance covered in the last second and add it to a global odometer. This would give a pretty accurate figure. Not really 100% accurate because when in a curve, it would still compute only the straight line distance of that second but so close anyway. It could possibly beat some cars odometer accuracy.

For the distance left to cover on a road, this is another ball game. Personnaly I calculate around 1.3 times the distance of the straight line. But this is not accurate at all. To get accuracy would require some huge databases and lots and lots of programming. You could also use Google to get the road distance and input it to the app before starting then substract this from the distance covered. I wonder how accurate it could be.

Google road distance to Anchorage airport from Montreal is 6716 Km. The aerial distance is 5026 Km. The road distance is then 1.34 times the aerial distance.

Edited September 15, 2012 by AlainB