and some more options... dat <- structure(list(ID = structure(c(1L, 1L, 1L, 2L, 2L, 2L, 2L), .Label = c("1", "2"), class = "factor"), time = c(1, 2, 3, 1.5, 4, 5.5, 6), y = c(1.4, 2, 2.5, 2.3, 4.5, 1.6, 2)), .Names = c("ID", "time", "y"), row.names = c(NA, -7L), class = "data.frame")
library(lattice) xyplot(y ~ time|ID, data = dat, type = 'l') xyplot(y ~ time, data = dat, group = ID, type = 'l') library(ggplot2) qplot(time, y, data = dat, facets = .~ID, geom = 'line') qplot(time, y, data = dat, group = ID, color = ID, geom = 'line') hth, Kingsford Jones On Mon, Aug 23, 2010 at 1:58 PM, Lei Liu <liu...@virginia.edu> wrote: > Hi there, > > I want to make trajectory plots for data as follows: > > ID time y > 1 1 1.4 > 1 2 2.0 > 1 3 2.5 > 2 1.5 2.3 > 2 4 4.5 > 2 5.5 1.6 > 2 6 2.0 > > ... > > That is, I will plot a growth curve for each subject ID, with y in the y > axis, and time in the x axis. I would like to have all growth curves in the > same plot. Is there a simple way in R to do it? Thanks a lot! > > Lei Liu > Associate Professor > Division of Biostatistics and Epidemiology > Department of Public Health Sciences > University of Virginia School of Medicine > > http://people.virginia.edu/~ll9f/ > > ______________________________________________ > R-help@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. > ______________________________________________ R-help@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.