Hi, I'm sorry for not explaining well. I'm trying to do my best, but it's alittle complicated for me. I will send what I've tried but I think I should also provide some files to make possible for you to run the codes I'm running, but i couldn't find a way to do it. I have 2 rasters to represent environmental characteristics of my area (slasc.asc and weasc.asc). I also have a raster containing the cost of reaching every place in the area (euc_.asc). The function "clhs" allows to sample in places according to lowest-reaching costs, it means the clhs will choose points where is easier to go. To make this, I should use the code
res <- clhs(s, size = 30, iter = 2000, progress = FALSE, simple = FALSE, cost = "cost"). Then the R returns the error: Error in .local(x, ...) : Could not find the cost attribute I don't know what i'm doing wrong. I was wondering if somebody knows what I should try. The R-help says the cost is a character giving the name or an integer giving the index of the attribute in x that gives a cost that can be use to constrain the cLHS sampling. If NULL (default), the cost-constrained implementation is not used. Below it's the codes I'm using: require(raster) require(clhs) require(proj4) require(rgdal) # 1 - load the data r1<-raster("D:/Sg/Lavr/R/slasc.asc") r2<-raster("D:/Sg/Lavr/R/weasc.asc") #2 - load cost raster # I'M NOT SURE IF THIS STEP IS CORRECT rcost<-raster("D:/Sg/Lavr/R/euc_.asc") #3 - set spatial references projection(r1) <- "+proj=utm +zone=23 +south +ellps=WGS84 +datum=WGS84 +units=m +no_defs" projection(r2) <- "+proj=utm +zone=23 +south +ellps=WGS84 +datum=WGS84 +units=m +no_defs" projection(rcost) <- "+proj=utm +zone=23 +south +ellps=WGS84 +datum=WGS84 +units=m +no_defs" #4 - creates a multiple raster*object s = stack(r1, r2, rcost) #5 - Conditional latin hypercube sampling res <- clhs(s, size = 30, iter = 2000, progress = FALSE, simple = FALSE, cost = "rcost") Error in .local(x, ...) : Could not find the cost attribute. Thank you! Sergio -- View this message in context: http://r.789695.n4.nabble.com/Conditioned-Latin-Hypercube-Sampling-within-determined-distance-tp4633974p4634457.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.