Scatterplot Showing All Points
Wayne Aldo Gavioli wrote:
Hello all, I'm trying to graph a scatterplot of a large (5,000 x,y coordinates) of data with the caveat that many of the data points overlap with each other (share the same x AND y coordinates). In using the usual "plot" command,
plot(education, xlab="etc", ylab="etc")
it seems that the overlap of points is not shown in the graph. Namely, there are 5,000 points that should be plotted, as I mentioned above, but because so many of the points overlap with each other exactly, only about 50-60 points are actually plotted on the graph. Thus, there's no indication that Point A shares its coordinates with 200 other pieces of data and thus is very common while Point B doesn't share its coordinates with any other pieces of data and thus isn't common at all. Is there anyway to indicate the frequency of such points on such a graph? Should I be using a different command than "plot"?
Hi Wayne, While this is not a really pretty picture, you can get a viewable plot with count.overplot if the first two elements of "education" are named "x" and "y" and they are the coordinates you want to plot. Otherwise, pass the x and y coordinates separately. library(plotrix) count.overplot(education, tol=c(diff(range(education$x))/10, diff(range(education$y))/10)) Jim