Building a vector of random sf st_points
On 21/12/16 17:25, Pierre Racine wrote:
Hi,
Hi Pierre!
Very new to spatial R. I'm trying to find the best way to build a sf dataframe of random points inside an extent. I built a matrix of random coordinates and now I try to convert this matrix to a vector of st_point. I was expecting that something like: PTS <- matrix(seq(1,6), 3, 2)
st_sfc(lapply(seq_len(nrow(PTS)), function(i) st_point(PTS[i,])))
Geometry set for 3 features geometry type: POINT dimension: XY bbox: xmin: 1 ymin: 4 xmax: 3 ymax: 6 epsg (SRID): NA proj4string: NA POINT(1 4) POINT(2 5) POINT(3 6)
ptsdf <- apply(PTS, 1, st_point) would work but it doesn't. Why?
apply wants to to mold the output into a matrix; it can, and so it does. We want a list of POINT objects, so need to use lapply.
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