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

Edzer Pebesma edzer.pebesma at uni-muenster.de
Sat Aug 31 22:05:11 CEST 2013


-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

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
>>> mailing list R-sig-Geo at r-project.org 
>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>> 
> 
> [[alternative HTML version deleted]]
> 
> _______________________________________________ R-sig-Geo mailing
> list R-sig-Geo at r-project.org 
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
> 

- -- 
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
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.11 (GNU/Linux)
Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/

iQEcBAEBAgAGBQJSIkx3AAoJEM1OCHCtOnfx2X0IAIPFc/Ut4cxqNcdFfXn2bFgQ
++HgCVm2EXHp6gqGNnGT4vD+Wn8DnXXd483alUFLD6SLxIqtI51DSTSEGy1p6ZkI
1bbKFdGKHmrOgXXf98nmBUBxHJGVrCU4M+aDVmHA2c5QhmEeqM/JnoGijL2pPHpH
SuK6HcBEqhL36jgtKF/uJKnMf4nEEFtP6lQ7UAVuhzADZ3nMR36zl+o/EsoHtwbt
uFcjDpP+qPh2S1wXd/y90lj8d1Pj3tQXNONvbOTgVthealPGBZxCTSSPbedhIV4w
jSfk2ded7QICCR0AoGRFcxV21SR0a5FrXpWjIfgWyWRg+RWq+5Dxdoxnu7ozOIs=
=hPBa
-----END PGP SIGNATURE-----



More information about the R-sig-Geo mailing list