Hi I'm trying to analyse some data and need to set the geographic coordinate system before I can do the analysis. I've been trying to use the project command in rgdal but keep getting an error message saying: Error in project(locationsMatrix, PROJECTION.OUT) : latitude or longitude exceeded limits ( PROJECTION.OUT <- "+proj=aea +lat_1=-18 +lat_2=-36 +lat_0=0 +lon_0=132 +x_0=0 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs") I know that I'm using the right proj4 format (got it from the espy file in the Proj4 data directory) and I know that the datum is correct as I often use it in GIS (GDA94; Australia Albers). Before using the project command I have a series of commands to make my raw input (a csv file) into a matrix with only the two columns of co-ordinates. There doesn't seem to be any problem in the matrix either. I'm really confused as to what the problem could be. I've used this command successfully for other datasets. Thanks in advance of any help/suggestions -- View this message in context: http://r.789695.n4.nabble.com/problem-with-project-command-in-rgdal-tp3914203p3914203.html Sent from the R help mailing list archive at Nabble.com.
problem with project command in rgdal
3 messages · Michael Sumner, kalee
Hello, this question is more suitable for the R-Sig-Geo mailing list, so you could consider posting there in future. Read the information for that list here: https://stat.ethz.ch/mailman/listinfo/r-sig-geo Comments below.
On Tue, Oct 18, 2011 at 3:11 PM, kalee <kathryn.lee1 at students.mq.edu.au> wrote:
Hi I'm trying to analyse some data and need to set the geographic coordinate system before I can do the analysis. I've been trying to use the project command in rgdal but keep getting an error message saying: Error in project(locationsMatrix, PROJECTION.OUT) : ?latitude or longitude exceeded limits
The message is pretty explicit so, I would check the coordinates themselves, try range(locationsMatrix[,1]) and range(locationsMatrix[,2]) and see that they are sensible for longitude and latitude respectively - project() expects a 2 column matrix with lon, lat in that order.
( PROJECTION.OUT <- "+proj=aea +lat_1=-18 +lat_2=-36 +lat_0=0 +lon_0=132 +x_0=0 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs") I know that I'm using the right proj4 format (got it from the espy file in the Proj4 data directory) and I know that the datum is correct as I often use it in GIS (GDA94; Australia Albers).
You must mean the "epsg" file - it stands for "European Petroleum Survey Group" http://www.epsg.org/.
Before using the project command I have a series of commands to make my raw input (a csv file) into a matrix with only the two columns of co-ordinates. There doesn't seem to be any problem in the matrix either. I'm really confused as to what the problem could be. I've used this command successfully for other datasets.
Please share the code in full, since it might hide obvious problems that others could see. Providing a summary of the locationsMatrix columns, for at least their range (min/max) will probably suffice. They may simply not be in the range you expect, or they may be in the wrong order for longitude / latitude as mentioned above. Please also tell use your version of R and at least the version of rgdal, sessionInfo() gives a good summary. Cheers, Mike.
Thanks in advance of any help/suggestions -- View this message in context: http://r.789695.n4.nabble.com/problem-with-project-command-in-rgdal-tp3914203p3914203.html Sent from the R help mailing list archive at Nabble.com.
______________________________________________ R-help at r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Michael Sumner Institute for Marine and Antarctic Studies, University of Tasmania Hobart, Australia e-mail: mdsumner at gmail.com
Hi Mike Thanks for your comments. I had the code trying to project() the lat, long so all fixed now. Thanks for your help and pointing out the R-sig-Geo mailing list which I'll use in the future should I have other questions. Thanks Kate -- View this message in context: http://r.789695.n4.nabble.com/problem-with-project-command-in-rgdal-tp3914203p3917124.html Sent from the R help mailing list archive at Nabble.com.