[R-sig-Geo] generating coordinates at equal geographical distances

[Edzer Pebesma]

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John, as an alternative you may want to look into sp::spsample, using
type "Fibonacci"; the paper describing this is

Alvaro Gonzalez, 2010. Measurement of Areas on a Sphere Using
Fibonacci and Latitude-Longitude Lattices. Mathematical Geosciences
42(1), p. 49-64


On 08/28/2013 07:27 PM, john d wrote:
> Ok, I'll be more explicit :)
> 
> If I want to generate random coordinates across North America by
> uniformly sampling latitudes and longitudes, the geographical
> distance between these coordinates would decrease towards higher
> latitudes. I'd like to be able to generate coordinates (e.g. a
> grid) such that the geographical distances between coordinates
> would be constant regardless of latitude.
> 
> 
> 
> On Wed, Aug 28, 2013 at 12:04 PM, Barry Rowlingson < 
> b.rowlingson at lancaster.ac.uk> wrote:
> 
>> You will find that any two coordinates are equidistant from each
>> other...
>> 
>> So my suggestion is you need to expand you question a bit more!
>> :)
>> 
>> On Wed, Aug 28, 2013 at 3:49 PM, john d <dobzhanski at gmail.com>
>> wrote:
>>> Dear all,
>>> 
>>> I need to generate coordinates that are equidistant, regardless
>>> of latitude. Any suggestions?
>>> 
>>> Thanks!
>>> 
>>> John
>>> 
>>> [[alternative HTML version deleted]]
>>> 
>>> _______________________________________________ R-sig-Geo
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>> 
> 
> [[alternative HTML version deleted]]
> 
> _______________________________________________ R-sig-Geo mailing
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> 

- -- 
Edzer Pebesma
Institute for Geoinformatics (ifgi), University of Münster
Heisenbergstraße 2, 48149 Münster, Germany. Phone: +49 251
83 33081, Fax: +49 251 8339763 http://ifgi.uni-muenster.de
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