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

[Robert J. Hijmans]

And you can compare the results with those of the
'regularCoordinates' function in geosphere.  Robert

On Sat, Aug 31, 2013 at 1:05 PM, Edzer Pebesma
<edzer.pebesma at uni-muenster.de> wrote:
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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]]
>>>>
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>>
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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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