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rrasterr-grid

raster package: Lines around each cell

I want to have black lines around each cell of a raster. Below is the example data. I mean, instead of this frame/borderless cells

enter image description here

I want this(cells with borders)

enter image description here How can I achieve this?

 library(raster)
 require(graphics)
 require(grDevices)
 library(colorRamps)

 data<-matrix(c(1,0.4,0.5,0.8,-0.9,0.3,-0.89,-0.62,-0.33),ncol=3)

  r <- raster(nrows=dim(data)[1],ncols=dim(data)[2],
               xmn=-1,xmx=1,ymn=-1,ymx=1)
  r[]<-data
  setValues(r,factor(data))
  plot(r,col=c(topo.colors(200)),axes=FALSE,box=FALSE)
Solution

  • You can use rasterToPolygons:

    plot(r, col=c(topo.colors(200)), axes=FALSE, box=FALSE)
plot(rasterToPolygons(r), add=TRUE, border='black', lwd=1)