Thanks Jim.

You're right; that sounds much simpler and it makes much more sense.

SR

Steven H. Ranney


On Thu, Apr 18, 2013 at 3:08 PM, Robert J. Hijmans <r.hijmans@gmail.com>wrote:

> Steven,
>
> It would be much simpler to compute the distances between the two sets of
> points and then ask if there are any that are less than your threshold.
>
> a <- cbind(c(1,5,55),c(3,7,20))
> b <- cbind(c(4,2,8,65),c(50,-90,20,32))
>
> library(raster)
> d <- pointDistance(a, b, longlat=TRUE)
> any(d < 200)
>
> Robert
>
>
>
>
> On Thu, Apr 18, 2013 at 1:58 PM, Steven Ranney <steven.ranney@gmail.com>wrote:
>
>> I'm new to the world of spatial analyses in R.  I've done some searching
>> and reading around, but haven't found answer to my question.  I may not be
>> looking in the correct place.
>>
>> I have a series of references lat/long pairs (listA) that I'd like to
>> import into R and have R create a 200m buffer around these points.  I'd
>> then like to bring in a second list (listB) of lat/long pairs that may or
>> may not correpond with the reference points and use the over() function to
>> find out if listB falls within 200m of listA.
>>
>> I'm guessing that the work flow would be to bring in listA, somehow draw
>> the buffer around the points, and export it as a shapefile, THEN bring in
>> listB and run the over() function.
>>
>> Is this a logical process and can it even be done?
>>
>> Thanks for your help -
>>
>> SR
>> Steven H. Ranney
>>
>>         [[alternative HTML version deleted]]
>>
>> _______________________________________________
>> R-sig-Geo mailing list
>> R-sig-Geo@r-project.org
>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>
>
>

	[[alternative HTML version deleted]]

