1

I try to fit my shape to the google map.

require(rgdal)

in.dir <- getwd()

    sh <- readOGR(in.dir, layer = "Ytor", 
p4s = "+proj=tmerc +lat_0=0 +lon_0=15.80827777777778 +k=1 +x_0=1500000 +y_0=0 +ellps=bessel +units=m +no_defs")


sh@proj4string 
sh2 <- spTransform(sh, CRS("+proj=longlat +datum=WGS84 +ellps=WGS84 +no_defs"))

sh2@proj4string 

 sh2.df <- fortify(sh2)

library(ggplot2)
library(ggmap)

swe <- get_map(location = c(15.3, 63.63, 15.5, 63.68),  maptype = 'satellite')
ggmap(swe) + geom_polygon(aes(x = as.numeric(long), y = as.numeric(lat), group = group), data = df, color = "white", fill = "white", alpha = 0.1) 

Finally I got the map as belowenter image description here

The borders of the shape are not going as the ggmap borders. What did I wrong that the borders does not fit?

  • I once experienced problems with the projection of my data when using readOGR alongside with Google Maps data. Try to manually add the projection of layer "Ytor" (argument p4s) to readOGR and crosscheck the visualization afterwards. – fdetsch Sep 17 '15 at 8:54
  • Do I get it right? I should set the p4s argument in the function readOGR. How the argument should look like? – Mateusz1981 Sep 17 '15 at 10:18
  • Just like the output of proj4string, I suppose. It's detailed in ?readOGR. At least it's worth trying, helped me out back then. – fdetsch Sep 17 '15 at 12:53
  • @fdetsch I edited question. I added argument p4sin the readOGR function but it did not help? Did I make it right? – Mateusz1981 Sep 18 '15 at 5:37
  • Yeah, it's correct. As I said, it was worth trying. Maybe somebody else knows what the problem is then. – fdetsch Sep 18 '15 at 5:54
0

Your projection string has no towgs84 parameters.

Assuming your data is in EPSG:3021 RT90 2.5 gon V, it should be:

+proj=tmerc +lat_0=0 +lon_0=15.80827777777778 +k=1 +x_0=1500000 +y_0=0 +ellps=bessel +towgs84=414.1,41.3,603.1,-0.855,2.141,-7.023,0 +units=m +no_defs

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