Fix variogramST.STIDF

[darentsai]

gstat/R/variogramST.R

Line 234 in 8335d8e

tmpInd[,3] <- apply(tmpInd[,1:2,drop=FALSE], 1, function(x) spDists(data@sp[x[1]], data@sp[x[2]+x[1],]))

With a moderately large data and unspecified twindow, tmpInd will have countless rows, and apply on it is literally time-consuming. I adapt it for a vectorized computation and the efficiency is much improved.

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gstat/R/variogramST.R

Lines 255 to 256 in 8335d8e

	gamma[j,i] <- 0.5*mean((data[,,colnames(m)[1]]@data[indSp[,1],1] - data[,,colnames(m)[1]]@data[indSp[,1]+indSp[,2],1])^2,
	na.rm=TRUE)

data[indSp[,1],1] extracts only one column. For a data.frame, the default is to drop if only one column is left, and the result reduces to a vector. However, for a tibble, it's not the default. data[indSp[,1],1] is still a tibble, and hence passing a tibble into mean returns NA. I add drop=TRUE to coerce tibble to drop.