UTM problem
Hi, I double-checked your results with an online conversion tool (http://www.rcn.montana.edu/resources/tools/coordinates.aspx) and got the same answer. That means that your R code is fine, and there's something wrong with the original data. If possible, you should check with the source. There could be a problem with the metadata, or with the data themselves. Sarah
On Wed, Oct 13, 2010 at 9:37 AM, Werner W. <pensterfuzzer at yahoo.de> wrote:
Hi, this questions is not really about R but it would be great if somebody could point me to a forum or so where I can get help with this. I only know a few basics about GIS and have a problem with some UTM coordinates from a survey. Coordinates are given as, e.g. 3258843 ? ? 32780 which are supposedly zone 36N on system WGS84 (according to the documentation). If I convert it to long/lat using gdal:
require(rgdal)
SP <- SpatialPoints(cbind(X=3258843, Y=32780),proj4string=CRS("+proj=utm
+zone=36 +ellps=WGS84"))
spTransform(SP, CRS("+proj=longlat +ellps=WGS84")) # x1=longitude x2=lat
SpatialPoints: ? ? ? ? ? X ? ? ? ? Y [1,] 57.0489 0.2706471 Coordinate Reference System (CRS) arguments: +proj=longlat +ellps=WGS84 The point should be close to Kampala which has the coordinates 0.3?, 32.633333? and UTM 36N 459199 33160 on WGS84. My data's easting seems quite off. Has anybody an idea what I am doing wrongly? Thanks so much, ?Werner
Sarah Goslee http://www.functionaldiversity.org