Michael Friendly wrote: > Thanks Duncan, > That is almost exactly what I want, except I want time to > go in the normal order, not backwards, so: > > # plot on reverse log scale > years1500 <- runif(500, 1500, 1990) # some fake data > x <- -log(2000-years1500) > from <- -log(2000-1990) > to <- -log(2000-1500) > plot(density(x, from=from, to=to), axes=F) > rug(x) > > labels <- pretty(years1500) > labels <- labels[labels<2000] > axis(1, labels, at=-log(2000-labels)) > > minorticks <- pretty(years1500, n=20) > minorticks <- minorticks[minorticks<2000] > axis(1, labels=FALSE, at=-log(2000-minorticks), tcl=-0.25) > > axis(2) > box() > > -Michael > > Duncan Murdoch wrote: > > >>On 7/6/2005 3:36 PM, Michael Friendly wrote: >> >> >>>I'd like to do some plots of historical event data on a reverse log >>>scale, started, say at the year 2000 and going >>>backwards in time, with tick marks spaced according to >>>log(2000-year). For example, see: >>> >>>http://euclid.psych.yorku.ca/SCS/Gallery/images/log-timeline.gif >>> >>>As an example, I'd like to create a density plot of such data with the >>>horizontal axis reverse-logged, >>>a transformation of this image: >>>http://euclid.psych.yorku.ca/SCS/Gallery/milestone/Test/mileyears1.gif >>> >>>Some initial code to do a standard density plot looks like this: >>> >>>mileyears <- read.csv("mileyears3.csv", skip=1, >>>col.names=c("key","year","where","add","junk")) >>>mileyears <- mileyears[,2:4] >>> >>>years <- mileyears$year >>>years1500 <- years[years>1500] >>>dens <- density(years1500, from=1500, to=1990) >>>plot(dens) >>>rug(years1500) >>> >>>I could calculate log(2000-year), but I'm not sure how to do the >>>plotting, do some minor tick marks >>>and label the major ones, say at 100 year intervals. >> >> >>I think you'll have to do everything explicitly. That is, something >>like this: >> >>years1500 <- runif(500, 1500, 1990) # some fake data >>x <- log(2000-years1500) >>from <- log(2000-1990) >>to <- log(2000-1500) >>plot(density(x, from=from, to=to), axes=F)
Careful there: from > to, and that seems to have messed up density. Since the code assumes from < to, we should have a test and an error message (or a swap). Duncan Murdoch >>rug(x) >> >>labels <- pretty(years1500) >>labels <- labels[labels<2000] >>axis(1, labels, at=log(2000-labels)) >> >>minorticks <- pretty(years1500, n=20) >>minorticks <- minorticks[minorticks<2000] >>axis(1, labels=FALSE, at=log(2000-minorticks), tcl=-0.25) >> >>axis(2) >>box() >> >>Duncan Murdoch > > ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
