[R-sig-Geo] Interpolating with barrier in R

[Camilo Mora]

Hi everyone,

I have some point data over the entire world that i want to  
interpolate to a raster with resolution of 1 degree.

I have been able to work the code for IDW and Spline in the raster  
package in R....but I wonder if there is a way to include a barrier to  
the interpolations?. In ArcGis several interpolations allow for the  
use of barriers beyond which interpolation is stopped. Is there an  
analogous feature in r?

I note that the results of IDW and Spline interpolate over land and my  
worry is that in certain places like the panama, data from the pacific  
may be used to interpolate the caribbean and viceversa.

Any advice will be greatly appreciate.

Thanks,

Camilo

Camilo Mora, Ph.D.
Department of Geography, University of Hawaii
Currently available in Colombia
Phone:   Country code: 57
          Provider code: 313
          Phone 776 2282
          From the USA or Canada you have to dial 011 57 313 776 2282
http://www.soc.hawaii.edu/mora/