Dear friends, I had a point pattern dataset, whose locations was defined by lat./long.. In the past, I used ARCGIS to specify its coordinate system and the projection method, now i want to do it in R. I don't know how to do it, because it needs me to specify the *Geographic Coordinate System and the Projected Coordinate System.* Maybe i mistake the information in ARCGIS and only the projection method need to be specified because of my poor knwledge on coordiante systems.
---------------------------------------------------The information in ARCGIS after projecting the dataset------- Geometry Type: Point *Geographic Coordinate System:* #specify the coordinate system GCS_Xian_1980 Datum: D_Xian_1980 Prime Meridian: 0 *Projected Coordinate System:* Xian_1980_3_Degree_GK_CM_117E #specify the projection method Projection: Gauss_Kruger False_Easting: 500000.00000000 False_Northing: 0.00000000 Central_Meridian: 117.00000000 Scale_Factor: 1.00000000 Latitude_Of_Origin: 0.00000000 Linear Unit: Meter (1.000000) ---------------------------------------------------------------------------------------------------------------------------- mapproject(x, y, projection="", parameters=NULL, orientation=NULL) *#only allows us to define the projected coordinate system Anybody knows how to finish it in R? Maybe rgdal() can it, but it's a liitle difficult for me*. *Example of my dataset:* ID CLASS SOILTEM AIRTEM GHEIGHT H *LAT LONG* 1 1 19 20 50 30.61688 117.4140 2 1 19 21 65 30.61686 117.4140 3 2 20 22 55 30.61680 117.4139 4 3 20 26 10 30.61675 117.4139 5 4 20 23 75 30.61679 117.4140 6 1 21 21 55 30.61685 117.4141 BTW, when i load the package rgdal, the following errors appear,*where is the wrong*? Does it mean i need to use the R2.4.0 version? error in load(dataFile, ns) : ReadItem uncorrect:no class 25 Warning message: package'rgdal'is build with R2.4.0 error: package'rgdal' R's input code fail error: 'rgdal'package/name space load fail, -------------------------------package information ---------------------------- R : Version 2.3.1 (2006-06-01) rgdal_0.5-1 --------------------------------------------- -- With Kind Regards, oooO::::::::: (..)::::::::: :\.(:::Oooo:: ::\_)::(..):: :::::::)./::: ::::::(_/:::: ::::::::::::: [***********************************************************************] Zhi Jie,Zhang ,PHD Tel:86-21-54237149 [EMAIL PROTECTED] Dept. of Epidemiology,school of public health,Fudan University Address:No. 138 Yi Xue Yuan Road,Shanghai,China Postcode:200032 [***********************************************************************] oooO::::::::: (..)::::::::: :\.(:::Oooo:: ::\_)::(..):: :::::::)./::: ::::::(_/:::: ::::::::::::: [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo