YIHSU CHEN <yschen <at> jhu.edu> writes: > > Dear Helpers: > > I'm trying to use packages "maps" and "mapdata" (see blow) to display the research resutls on map > (Mid-Atlantic region). In particular, I need to mark a number of points in the map by giving their latitude > and longitude information. For instance, I would like to mark a point on (long, lat) =(75.56027,
You can use library(mapproj) and the function mapproject() to do this. mapproject converts longitude and latitude to x and y projections on a plot, as in the following: map('usa') locations <- mapproject(longitude, latitude) points(locations) -Alan -- -Alan Schussman / Graduate Associate University of Arizona Department of Sociology ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html