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Topic: units for great circle distance
Replies: 5   Last Post: May 29, 2014 2:06 PM

 Messages: [ Previous | Next ]
 Jonathan W Smith Posts: 90 Registered: 12/17/10
Re: units for great circle distance
Posted: May 29, 2014 1:06 PM

dpb <none@non.net> wrote in message <lm7ogh\$vn3\$1@speranza.aioe.org>...
> On 5/29/2014 10:21 AM, Jonathan W Smith wrote:
> ... [top posting repaired]...
>

> > dpb <none@non.net> wrote in message <lm5tq8\$kgd\$1@speranza.aioe.org>...
> >> On 5/28/2014 3:29 PM, Jonathan W Smith wrote:
> >> > Hello
> >> > What are the units for the result of the greatCircleDistance function?

> >>
> >> Dependent on units of what you input...

>
> > Good morning:
> >
> > My longitude and latitude are degrees. How does the function know what
> > units you are putting in? If I put in miles, will it output miles? If I
> > put in the number 10 how does in know its no miles vs km?
> >
> > Thanks
> >
> > Jonathan

>
> Guess better find out which function you're actually using; there is no
> greatCircleDistance() function in current documentation nor at the File
> Exchange, I just made a deductive conclusion from the name of the function.
>
> The Mapping Toolbox function distance() returns an arc length in degrees
> by default, optionally in radians. You convert to distance based on
> diameter.
>
> Check the documentation on the function you're using, specifically, for
> its assumptions.
>
> --

There are two great circle distance functions on the file exchange:

http://www.mathworks.com/matlabcentral/fileexchange/36695-corresponding-points-through-mdl/content/Functions3D/GreatCircleDistance.m

http://www.mathworks.com/matlabcentral/fileexchange/23026-compute-the-great-circle-distance-between-two-points/content/greatCircleDistance.m

Date Subject Author
5/28/14 Jonathan W Smith
5/28/14 dpb
5/29/14 Jonathan W Smith
5/29/14 dpb
5/29/14 Jonathan W Smith
5/29/14 dpb