Interesting problem. I would discretize the x-values and interleave them. Lines from one dataset still overlap, so you see high- density and low-density regions, but lines from the other dataset are drawn into the interval. Like so:
interleave <- function(x, MIN, MAX, N, nChannel = 2, channel) { isp <- seq(MIN, MAX, length.out = N + 1) # interleave support points offset <- ((isp[2] - isp[1]) / nChannel) * (channel - 1) # offset for channel # round x to the nearest support point and add the channel specific offset x <- isp[round(as.numeric(cut(x, breaks = N)))] + offset return(x) } xi <- min(EU$DAX) xa <- max(EU$DAX) plot(interleave(EU$DAX, MIN=xi, MAX=xa, N=130, channel=1 ), EU$CAC, col = "#6600EE07", type = "h", ylim = c(0,6000), xlab = "DAX") points(interleave(EU$DAX, MIN = xi, MAX = xa, N = 130, channel = 2 ), EU$FTSE, col = "#EE000007", type = "h") Cheers, B. > On 2018-05-31, at 16:56, Ed Siefker <ebs15...@gmail.com> wrote: > > I have two chromatograms I want plotted on the same axes. > I would like the plots to be transparent, so the first chart is > not obscured. > > I have tried adjustcolor(..., alpha.f=0.3), the problem is that > my chromatogram is so dense with datapoints that they > overlap and the entire graph just ends up a solid color. The > second histogram still obscures the first. > > Consider this example: > > > col1 <- adjustcolor("red", alpha.f=0.3) > col2 <- adjustcolor("blue", alpha.f=0.3) > EU <- data.frame(EuStockMarkets) > with(EU, plot(DAX, CAC, col=col2, type="h", ylim=c(0,6000))) > par(new=TRUE) > with(EU, plot(DAX, FTSE, col=col1, type="h", ylim=c(0,6000))) > > The density of the red plot around 2000 completely obscures the blue > plot behind it. > > What I would like to do is plot both plots in solid colors, then alpha > the entire thing, and then overlay them. Or some other method that > achieves a comparable result. > Thanks > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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 -- To UNSUBSCRIBE and more, see 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.