How do I determine distance between coordinates?

May 27, 2003

Can someone tell me how to determine a distance between 2 coordinates? For example, if I have N31'01.977 W097'37.377 and N31'01.769 W097'37.332, how would I know how far apart these two are?

May 27, 2003

Try this:

http://williams.best.vwh.net/gccalc.htm

If that doesn't do what you want, go to google and search for 'great circle distance calculator'

... Two roads diverged in a wood, and I--

I took the one less traveled by, ...

unclerojelio

2.3k · May 27, 2003

1. Enter the two coords as waypoints

2. Create a route with the two waypoints.

3. In the routes screen, highlight the second point and the distance and bearing will be shown.

Set your nav units to yards if you want to read yards under a mile, or to feet if you want to read feet under a tenth of a mile.

May 27, 2003

If you use EasyGPS it will also calculate the distance between two point in a file. In fact, you can select a point and it will calculate the distance to all other points in that file, and allow you to sort by that distance.

Dave_W6DPS

My two cents worth, refunds available on request. (US funds only)

May 27, 2003

fwd/inv

This is good free software to do exactly what you want.

It's not a sport unless there is something dead in the back of the truck when you get home.

8.9k · May 27, 2003

Here's a java site that does it. Just enter in zeros if you aren't using that level of coordinates. In other words, if you have N 41° 51.237, enter 41 in the degrees, 51.237 in the minutes, and zero in the seconds.

Works every time. Too bad it also doesn't show in feet though.

Markwell

Chicago Geocaching

May 28, 2003

Thanks Markwell, that site was perfect! I've bookmarked it.

May 28, 2003

If you're interested, here's the formula for calculating your own distances.

This formula is formated for use in Excel as I do a lot of distance calulations for my job. (E911 Location stuff....)

=R*(ACOS((SIN(RADIANS(Lat1))*SIN(RADIANS(Lat2)))+(COS(RADIANS(Lat1))*COS(RADIANS(Lat2))*COS(RADIANS(Lon1)-RADIANS(Lon2)))))

R is the radius of the earth, so depending on which units you want the result in, you can set it for whatever you want. I normally set R to 6378 which is approximatly the radius of the earth in Kilometers give or take a few.

You can simply copy the formular right into Excel, load your units, reference the cells with the Lat's and Lon's which have to be in D.d (Decimal degrees) and you're on your way!

Here's a really good link explaining the distance calulation..

http://www.uottawa.ca/academic/arts/geographie/lpcweb/web2320/exercises/extras/greatcircle.htm

and some other links as well...

http://www.agso.gov.au/nmd/geodesy/datums/distance.jsp

http://www-2.cs.cmu.edu/~mws/lld.html

http://mathforum.org/library/drmath/view/51722.html

and another online calculator that accounts for the earth's "oblate spheroid" shape:

http://www.geocities.com/TheTropics/Shores/3098/distance.html