Jin,

I'd be willing to wager it can be done in R alone as someone is sure to
point out, but since you're using R (and so, willing to go the open source
route), you may be willing to take another step and use GRASS GIS (
http://grass.osgeo.org) — the wonderful thing about this is that your
problem is easily done in GRASS and it plays together very nicely with R.

Regards,
Tom

On Wed, Oct 3, 2012 at 8:38 PM, <Jin.Li@ga.gov.au> wrote:

> Dear list,
>
> I have two datasets: one is for point samples with lat and long
> information at accuracy of 0.001 degrees. Another is grid cells at a
> resolution of 0.0025 degrees. Both datasets are in txt format. Now I need
> to extract the lat and long information from the grid cell dataset for the
> point samples by assigning the lat and long of a grid cell to a sample
> point that falls in the grid cell. I usually get this done in ArcGIS. I was
> wondering if it is possible in R. I searched but failed to find a right
> function to implement this in R.
>
> Many thanks for any suggestions.
>
> Regards,
>
> Jin Li
> Spatial Modeller/Computational Statistician  |  Coastal, Marine and
> Climate Change Group
> Environmental Geoscience Division  |  GEOSCIENCE AUSTRALIA
> ____________________________________________________________
> Phone:  +61 2 6249 9899    Fax:  +61 2 6249 9999
> Email:  Jin.Li@ga.gov.au<mailto:Jin.Li@ga.gov.au>    Web:  www.ga.gov.au<
> http://www.ga.gov.au/>
> Cnr Jerrabomberra Avenue and Hindmarsh Drive Symonston ACT
> GPO Box 378 Canberra ACT 2601 Australia
> Applying geoscience to Australia's most important challenges
>
>
> Geoscience Australia Disclaimer: This e-mail (and files transmitted with
> it) is intended only for the person or entity to which it is addressed. If
> you are not the intended recipient, then you have received this e-mail by
> mistake and any use, dissemination, forwarding, printing or copying of this
> e-mail and its file attachments is prohibited. The security of emails
> transmitted cannot be guaranteed; by forwarding or replying to this email,
> you acknowledge and accept these risks.
>
> -------------------------------------------------------------------------------------------------------------------------
>
>
>         [[alternative HTML version deleted]]
>
> _______________________________________________
> R-sig-Geo mailing list
> R-sig-Geo@r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>



-- 

Thomas E Adams
National Weather Service
Ohio River Forecast Center
1901 South State Route 134
Wilmington, OH 45177

EMAIL:	thomas.adams@noaa.gov
VOICE:	937-383-0528
FAX:	937-383-0033

	[[alternative HTML version deleted]]

