[R] Subsampling out of site*abundance matrix

[B77S]

So, after thinking about this a bit, I realized that the previous solution
wasn't exactly what I needed.  I really needed replacement=F and to be able
to choose any sample size (n.sample) less than or equal to the site (row)
with the lowest total abundance.    

Anyway, I think this works.  Forgive me if I have misunderstood something
regarding the previous solutions output.  I do not pretend to be
intelligent.    Cheers!

############### start function ###############

RAND_L <- function(L.matrix, n.sample){
mainout <- vector("list")
for(i in 1:nrow(L.matrix)){
## decomposes species (1:ncol(L.matrix)) into a list of counts per each
out<- vector("list") 	
for(j in 1:length(L.matrix[i,])){
out[[j]] <- rep(names(L.matrix[i,])[j], L.matrix[i,j])
}
## puts previous loop products (counts) in a row
out2 <- vector()	
for(k in 1:length(out)){
out2 <- append(out2, as.character(unlist(out[k])))  
}
out3<- sample(out2, n.sample, replace=F)	
mainout[[i]] <- out3
mainout[[i]] <- factor(mainout[[i]], levels= colnames(L.matrix)) 	
}
finalout <- t(sapply(mainout, table)) 
rownames(finalout)<-rownames(L.matrix)	
return(finalout)	
}

################### end function ################## 


> RAND_L(abund2, 100)
      spA spB spC spD spa spF spG
site1  11  12  18   8   0  24  27
site2  24  24   0   0  27  25   0
site3   0   0   6  38   0   0  56
site4  27  20   0   0  16  37   0


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