I have two points of collection across 20 subjects (pre and post for each), so 20 pairs of data points. I would like to plot the actual raw data points for each subject for both pre and post and connect lines between these two points (20 in all) to depict real change between the two timepoints. I have tried using stripchart which adequately plots the two lines of subject data points. Attempting to use segments however has been difficult. It seems that the segments command gives too many coordiate points - so where segments has: x0, y0, x1, y1 I really only have two coordinates for each point - pre to post I am sure that I am misusing the command but not sure if I should continue to try with segments or if there is another command that would be more appropriate. As always, thanks for any help. [[alternative HTML version deleted]]
James Root wrote:> I have two points of collection across 20 subjects (pre and post for each), > so 20 pairs of data points. I would like to plot the actual raw data points > for each subject for both pre and post and connect lines between these two > points (20 in all) to depict real change between the two timepoints. > > I have tried using stripchart which adequately plots the two lines of > subject data points. Attempting to use segments however has been > difficult. It seems that the segments command gives too many coordiate > points - so where segments has: > > x0, y0, x1, y1 > > I really only have two coordinates for each point - > > pre to post > > I am sure that I am misusing the command but not sure if I should continue > to try with segments or if there is another command that would be more > appropriate. > > As always, thanks for any help.How about using matplot() instead? Something like this: matplot(t(matrix(runif(40), ncol=2)), type="b", col="black", lty=1, xaxt="n", pch=16) mtext(side=1, at=c(1,2), c("Pre","Post"))> [[alternative HTML version deleted]] > > ______________________________________________ > R-help at 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 > and provide commented, minimal, self-contained, reproducible code.-- Chuck Cleland, Ph.D. NDRI, Inc. 71 West 23rd Street, 8th floor New York, NY 10010 tel: (212) 845-4495 (Tu, Th) tel: (732) 512-0171 (M, W, F) fax: (917) 438-0894
James Root wrote:> I have two points of collection across 20 subjects (pre and post for each), > so 20 pairs of data points. I would like to plot the actual raw data points > for each subject for both pre and post and connect lines between these two > points (20 in all) to depict real change between the two timepoints. > > I have tried using stripchart which adequately plots the two lines of > subject data points. Attempting to use segments however has been > difficult. It seems that the segments command gives too many coordiate > points - so where segments has: > > x0, y0, x1, y1 > > I really only have two coordinates for each point - > > pre to post > > I am sure that I am misusing the command but not sure if I should continue > to try with segments or if there is another command that would be more > appropriate. > > As always, thanks for any help.Here is how you might use segments() and stripchart(): df <- data.frame(pre = runif(20), post = runif(20)) stripchart(x = list(df$pre, df$post), vertical=TRUE, group.names=c("Pre","Post")) for(i in 1:nrow(df)){segments(1, df$pre[i], 2, df$post[i])}> [[alternative HTML version deleted]] > > ______________________________________________ > R-help at 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 > and provide commented, minimal, self-contained, reproducible code.-- Chuck Cleland, Ph.D. NDRI, Inc. 71 West 23rd Street, 8th floor New York, NY 10010 tel: (212) 845-4495 (Tu, Th) tel: (732) 512-0171 (M, W, F) fax: (917) 438-0894