Thread Subject:

Draw an arc when two locations are known

Can anyone help me to draw an arc in between two locations. Latitude, longitude of the two locations and radius is known.

Thank you.

On 10/17/2010 11:30 PM, Nikhil Tej wrote:
> Can anyone help me to draw an arc in between two locations. Latitude, longitude of the two
 > locations and radius is known.
>
> Thank you.


check

http://www.mathworks.de/matlabcentral/newsreader/view_thread/141953

--Nasser

> Can anyone help me to draw an arc in between two
> locations. Latitude, longitude of the two locations
> and radius is known.
>
> Thank you.

In 3-dimensional space, two points and radius are
not enough information to uniquely determine the arc ...

Best wishes
Torsten.

"Nikhil Tej " <ng829709@ohio.edu> wrote in message <i9gphj$7cf$1@fred.mathworks.com>...
> Can anyone help me to draw an arc in between two locations. Latitude, longitude of the two locations and radius is known.
>
> Thank you.
- - - - - - - - - -
  In regard to the Feb. 20, 2007 thread Nasser refers to, the method I gave there was intended to apply to a plane surface. If your locations are sufficiently far apart that the earth's curvature becomes a factor, then those answers would become inaccurate. If the earth is assumed to be a perfect sphere, it would then be a problem in spherical geometry. (I assume the arc itself is also to lie entirely on the earth's surface.) Is that actually the problem you are posing?

  Also the method in the above thread only selects the arc that does not exceed pi radians and travels counterclockwise from a given initial point to a final point. In general there will be four arcs that pass through two given points with a given radius, whether we are on a plane surface or on a spherical surface.

Roger Stafford

On Oct 18, 7:30 pm, "Nikhil Tej " <ng829...@ohio.edu> wrote:
> Can anyone help me to draw an arc in between two locations. Latitude, longitude of the  two locations and radius  is known.
>
> Thank you.

The (free) m_map mapping toolbox at:
http://www.eos.ubc.ca/~rich/map.html
has a map projection called gnomonic that transforms all lines on a
map into great circle routes.

TideMan <mulgor@gmail.com> wrote in message <c1163acf-4e04-4327-b051-f6739fbed78f@r4g2000prj.googlegroups.com>...
> The (free) m_map mapping toolbox at:
> http://www.eos.ubc.ca/~rich/map.html
> has a map projection called gnomonic that transforms all lines on a
> map into great circle routes.
- - - - - - - -
  My impression is that, since Nikhil has taken the trouble to specify that the arc "radius is known", he is unlikely to be referring to the radius of the earth which is a more or less universally known quantity, and consequently the arcs in question would then not be great circle arcs.

Roger Stafford

"Roger Stafford" <ellieandrogerxyzzy@mindspring.com.invalid> wrote in message <i9j3a0$pht$1@fred.mathworks.com>...
> TideMan <mulgor@gmail.com> wrote in message <c1163acf-4e04-4327-b051-f6739fbed78f@r4g2000prj.googlegroups.com>...
> > The (free) m_map mapping toolbox at:
> > http://www.eos.ubc.ca/~rich/map.html
> > has a map projection called gnomonic that transforms all lines on a
> > map into great circle routes.
> - - - - - - - -
> My impression is that, since Nikhil has taken the trouble to specify that the arc "radius is known", he is unlikely to be referring to the radius of the earth which is a more or less universally known quantity, and consequently the arcs in question would then not be great circle arcs.
>
> Roger Stafford

Thank you so much Roger Stafford. I could complete the given task with your approach. Your assumption is right. I wanted to calcluate an arc between two locations which are near by and I wanted to consider 2 dimension. Your assumption was right and the formulae worked pretty good for me.
I have used 2 dimensional points and I have calculated latitude and longitude by using a different formulae with all the 2D points on the arc.
Thank you again.

Regards,
Nikhil

"Roger Stafford" <ellieandrogerxyzzy@mindspring.com.invalid> wrote in message <i9j3a0$pht$1@fred.mathworks.com>...
> TideMan <mulgor@gmail.com> wrote in message <c1163acf-4e04-4327-b051-f6739fbed78f@r4g2000prj.googlegroups.com>...
> > The (free) m_map mapping toolbox at:
> > http://www.eos.ubc.ca/~rich/map.html
> > has a map projection called gnomonic that transforms all lines on a
> > map into great circle routes.
> - - - - - - - -
> My impression is that, since Nikhil has taken the trouble to specify that the arc "radius is known", he is unlikely to be referring to the radius of the earth which is a more or less universally known quantity, and consequently the arcs in question would then not be great circle arcs.
>
> Roger Stafford

Thank you so much Roger Stafford. I could complete the given task with your approach. Your assumption is right. I wanted to calcluate an arc between two locations which are near by and I wanted to consider 2 dimension. Your assumption was right and the formulae worked pretty good for me.
I have used 2 dimensional points and I have calculated latitude and longitude by using a different formulae with all the 2D points on the arc.
Thank you again.

Regards,
Nikhil