Mao Jianfeng
2011-Nov-08 14:21 UTC
[R] from points in Lon/Lat to physical distance in dist class
Dear R-listers, Here, I would like to hearing helps from you. I have GPS data (multiple points in the geographic scale) in longitude/latitude. I intend to calculate distance (in kilometer) among such points and output the distance matrix in dist class. I have gotten some progress, but I still can not get final goal. Could please give me any directions/advice? This email cc. to Mr. Pierre, the author of BoSSA package. Thanks a lot in advance. Best wishes, Jian-Feng, Mao ######################################### What I have gotten are (1) distance among GPS points could be calculated by distGPS() function in BoSSA package. But, it can not output the distance in dist class. And, I do not know how to convert such distance matrix to dist class. (2) dist() function in base R can calculate distance among units and export it in dist class. But, it could not be used to work on points in lon/lat. (3) some dummy codes # (3.1) generate dummy points in lon/lat (in degree) points <- data.frame(lon=seq(95, 105),lat=seq(35, 45)) # (3.2) calculate distance between points using distGPS() library(BoSSA) Geodist<-distGPS(points) str(Geodist) class(Geodist) [[alternative HTML version deleted]]
David L Carlson
2011-Nov-08 14:35 UTC
[R] from points in Lon/Lat to physical distance in dist class
Look at distm() in package geosphere. ---------------------------------------------- David L Carlson Associate Professor of Anthropology Texas A&M University College Station, TX 77843-4352 -----Original Message----- From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf Of Mao Jianfeng Sent: Tuesday, November 08, 2011 8:22 AM To: r-help at r-project.org Cc: bossa.package at gmail.com Subject: [R] from points in Lon/Lat to physical distance in dist class Dear R-listers, Here, I would like to hearing helps from you. I have GPS data (multiple points in the geographic scale) in longitude/latitude. I intend to calculate distance (in kilometer) among such points and output the distance matrix in dist class. I have gotten some progress, but I still can not get final goal. Could please give me any directions/advice? This email cc. to Mr. Pierre, the author of BoSSA package. Thanks a lot in advance. Best wishes, Jian-Feng, Mao ######################################### What I have gotten are (1) distance among GPS points could be calculated by distGPS() function in BoSSA package. But, it can not output the distance in dist class. And, I do not know how to convert such distance matrix to dist class. (2) dist() function in base R can calculate distance among units and export it in dist class. But, it could not be used to work on points in lon/lat. (3) some dummy codes # (3.1) generate dummy points in lon/lat (in degree) points <- data.frame(lon=seq(95, 105),lat=seq(35, 45)) # (3.2) calculate distance between points using distGPS() library(BoSSA) Geodist<-distGPS(points) str(Geodist) class(Geodist) [[alternative HTML version deleted]] ______________________________________________ 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.