Thank you, this is the solution. I just replaced at4/20 by seq(0, max.yl, length.out=par("yaxp")[3]+1) so it should work with any scale. here is the final code that worked for me:
## R-Help 2014-05-28 asked by Bastian Pöschl solved by Gabor Grothendieck library("zoo") ## generate some smooth timeseries x1 <- c(38.2, 18.1, 83.2, 42.7, 22.8, 48.1, 81.8, 129.6, 52.0, 110.3) x2 <- c(2.2, 0.8, 0.7, 1.6, 0.9, 0.9, 1.1, 2.8, 5.1, 2.1) z1 <- zooreg(x1, start=as.POSIXct("2013-01-01 00:00:01"), frequency=0.0000006) z2 <- zooreg(x2, start=as.POSIXct("2013-01-01 00:00:20"), frequency=0.0000006) zt <- zooreg(rnorm(1050), start=as.POSIXct("2013-01-01 00:00:01"), frequency=0.00007) z<-merge(zt, z1, all = TRUE) z<-merge(z, z2, all = TRUE) Zf<-na.spline(z[,2:3], na.rm = FALSE) ## ## ## ## ## function to round up to a number divisible by n (2011 by Owen Jones) roundup <- function(x,n){ceiling(ceiling(x)/n)*n} ## ## ## ## ## Plot How to match secondary Y-axis ticks to primary ones plot(Zf$z1, ylim=c(0,signif(max(na.omit(Zf$z1)*1.05),2)), xlab="") ## use multiplication for even tick numbers and fake sekondary y-axis max.yl<-roundup(max(na.omit(Zf$z2)), par("yaxp")[3]) multipl.yl<-max(na.omit(Zf$z2))/max.yl multipl.z2<-signif(max(na.omit(Zf$z1)*1.05),2)/max.yl lines(Zf$z2*multipl.z2, lty=2) at4 <- axTicks(4) axis(4, at = at4, seq(0, max.yl, length.out=par("yaxp")[3]+1)) abline(h = at4, lty = "dotted", col="grey") The Result is a time series plot of two variables, with nice ticks at primary and secondary y-axis at the same height connected with reference lines and thus easy to read. 2014-05-28 12:56 GMT+02:00 Gabor Grothendieck <ggrothendi...@gmail.com>: > On Wed, May 28, 2014 at 4:28 AM, Bastian Pöschl <bstan0...@gmail.com> > wrote: > > Thank you for the quick reply, > > > > your advice wasn't exactly what I was looking for. > > The plot 1 of the example was ment to show my problem: > > the secondary axis has it's first tick at the intersection with the > x-axis > > whereas the primary y-axis shows a nice little offset. > > > > Using your advice i copied the y axis and tried to solve the Problem "by > > foot". Unfortunately the lable text isn't willing to center to the ticks > > > > Here is the code: > > > > ## R-Help 2014-05-28 > > > > ## Test second. Y-Axix > > library("zoo") > > > > ## generate some smooth timeseries > > x1 <- c(38.2, 18.1, 83.2, 42.7, 22.8, 48.1, 81.8, 129.6, 52.0, 110.3) > > x2 <- c(2.2, 0.8, 0.7, 1.6, 0.9, 0.9, 1.1, 2.8, 5.1, 2.1) > > > > z1 <- zooreg(x1, start=as.POSIXct("2013-01-01 00:00:01"), > > frequency=0.0000006) > > z2 <- zooreg(x2, start=as.POSIXct("2013-01-01 00:00:20"), > > frequency=0.0000006) > > zt <- zooreg(rnorm(1050), start=as.POSIXct("2013-01-01 00:00:01"), > > frequency=0.00007) > > > > z<-merge(zt, z1, all = TRUE) > > z<-merge(z, z2, all = TRUE) > > Zf<-na.spline(z[,2:3], na.rm = FALSE) > > ## ## ## ## > > > > ## Plot How to match secondary Y-axis ticks to primary ones > > plot(Zf$z1, ylim=c(0,signif(max(na.omit(Zf$z1)*1.05),2)), xlab="") > > > > ## function to round up to a number divisible by n (2011 by Owen Jones) > > roundup <- function(x,n){ceiling(ceiling(x)/n)*n} > > ## ## ## ## > > > > ## use multiplication for even tick numbers and fake sekondary y-axis > > max.yl<-roundup(max(na.omit(Zf$z2)), par("yaxp")[3]) > > multipl.yl<-max(na.omit(Zf$z2))/max.yl > > multipl.z2<-signif(max(na.omit(Zf$z1)*1.05),2)/max.yl > > lines(Zf$z2*multipl.z2, lty=2) > > axis(4, labels = FALSE) > > abline(h = axTicks(4), lty = "dotted", col="grey") > > lablist.y<-seq(0, max.yl, length.out=par("yaxp")[3]+1) > > > > ## my problem!! text doesn't center to the ticks > > text(y = seq(0, signif(max(na.omit(Zf$z1)*1.05),2), > > length.out=par("yaxp")[3]+1), > > par("usr")[2]+(par("usr")[2]-par("usr")[1])*0.025, labels = lablist.y, > srt = > > 90, pos = 4, xpd = TRUE) > > > > If the problem is to center the labels on the right y axis then try this: > > plot(Zf$z1, ylim=c(0,signif(max(na.omit(Zf$z1)*1.05),2)), xlab="") > lines(Zf$z2*multipl.z2, lty=2) > > at4 <- axTicks(4) > axis(4, at = at4, at4/20) > abline(h = at4, lty = "dotted", col="grey") > [[alternative HTML version deleted]]
______________________________________________ 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.