If the variables are spatially uncorrelated, it is a special case of what I provided, and you could specify the variography in terms of pure nuggets, and/or use a neighbourhood of 1 (or 0?).
As an alternative, fill the grids with data generated with function rmvnorm in package mvtnorm. I find it however hard to understand what you mean by a spatial cross-correlation index, especially the word spatial, when you do not want to address spatial autocorrelation of the variables themselves. -- Edzer Enrico R. Crema wrote: > Many Thanks, > But I guess explained very badly (sorry for this!!) what I need. I am > building an Agent Based Simulation and part of the model requires > series of two randomly generated raster maps, having a spatial > cross-correlation index ranging from -1 to +1. Clearly If I can > specify autocorrelation of each that will be even better, but at this > stage I just need two randomly generated surfaces with a > user-specified Cross-Correlation Index. Sorry again for the bad > explanation! > > Enrico > > --------------------------------------- > Enrico R. Crema > PhD Candidate > Institute of Archaeology, UCL > AHRC Centre for the Evolution of Cultural Diversity, UCL > http://www.cecd.ucl.ac.uk/people/?go1=91 > +44 7899093191 > [email protected] > [email protected] > > > > > > > > On 9 Oct 2009, at 07:49, Edzer Pebesma wrote: > >> Enrico, try >> >> library(gstat) >> demo(cosimulation) >> >> First part is on Gaussian simulation, the second on indicator >> simulations. >> >> Best regards, >> >> Enrico R. Crema wrote: >>> Dear All, >>> Is there any R function capable a set of two raster maps with a user- >>> defined spatial cross-correlation index (between the two rasters)? >>> Many Thanks, >>> Enrico Crema >>> --------------------------------------- >>> Enrico R. Crema >>> PhD Candidate >>> Institute of Archaeology, UCL >>> AHRC Centre for the Evolution of Cultural Diversity, UCL >>> http://www.cecd.ucl.ac.uk/people/?go1=91 >>> +44 7899093191 >>> [email protected] >>> [email protected] >>> >>> >>> >>> >>> >>> >>> >>> >>> [[alternative HTML version deleted]] >>> >>> _______________________________________________ >>> R-sig-Geo mailing list >>> [email protected] >>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo >>> >> >> -- >> Edzer Pebesma >> Institute for Geoinformatics (ifgi), University of Münster >> Weseler Straße 253, 48151 Münster, Germany. Phone: +49 251 >> 8333081, Fax: +49 251 8339763 http://ifgi.uni-muenster.de/ >> http://www.springer.com/978-0-387-78170-9 [email protected] >> > > -- Edzer Pebesma Institute for Geoinformatics (ifgi), University of Münster Weseler Straße 253, 48151 Münster, Germany. Phone: +49 251 8333081, Fax: +49 251 8339763 http://ifgi.uni-muenster.de/ http://www.springer.com/978-0-387-78170-9 [email protected] _______________________________________________ R-sig-Geo mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-geo
