edzer / sp

Classes and methods for spatial data
http://edzer.github.io/sp/
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Bbox issue #118

Open nephentes7 opened 2 years ago

nephentes7 commented 2 years ago

I am trying to run spsample, using country boundaries as spatial object (x). However, I need sample points/and grid covering a slighly larger AOI (of e.g. kind of buffering), using the same cellsize (to get overlapping points). Thus, I have changed only the bbox, creating a new matrix as below (nm2). However, the results, (points2) does not 'cover' the new bbox. Why? Maybe I am missing something...THANKS

"bb: bounding box of the sample domain; setting this to a smaller value leads to sub-region sampling"

points1 <- spsample(study_area, type = "hexagonal", cellsize = size) points2 <- spsample(study_area, type = "hexagonal", bb= bbox(nm2), cellsize = size)


size <- 0.179

original bbox of study area

minori <- c(-11.485695, 4.352916) maxori <- c(-7.365113, 8.551790) m <- cbind(minori, maxori) rnameso <- c("x","y") cnameso <- c("min", "max") nm <- matrix(m,nrow=2,byrow=FALSE,dimnames=list(rnameso,cnameso)) nm

new bbox ('buffering')

min <- c(-13.485695, 6.352916) max <- c(-9.365113, 10.551790)

m2 <- cbind(min, max) rnames <- c("x","y") cnames <- c("min", "max") nm2 <- matrix(m2,nrow=2,byrow=FALSE,dimnames=list(rnames,cnames)) nm2