David, It turns out that the 'at' argument takes the values 1,70,by=5, while the 'label' spans -36,33,by=5 Just took a little trial and error, but the graph now looks great. Cheers!
Jeremy jproville wrote: > > Hi, > > I'd really appreciate if someone could give me some help or advice about > this - I've tried everything I know and am clueless about how to proceed! > > I've written a script to import ASCII data of raster maps, bin them into > categories, calculate the mean values within these bins and plot the two > in a simple graph. I'm running into problems with my x axis, as R cannot > add the bin categories as labels and simply outputs the factor values of > the number of bins. > > In much more detail: > One set of data is fractional values for the amount of cropland in a > designated area (raster cell). The second is annual average temperature > data, in the same format. I import these using: > xRaw<-scan(".../Temp.txt") > yRaw<-scan(".../Cropland.txt") > > and then designate cells with values of -9999 as NAs: > x<-ifelse(xRaw==-9999,NA,xRaw) > y<-ifelse(yRaw==-9999,NA,yRaw) > > Then, I compile them into a 2 column data frame, and exclude the NA > values: > zRaw<-data.frame(x,y) > z<-na.exclude(zRaw) > > I am then left with data frame 'z' which is a refined list of data. Using > the 'cut' function, I assign each row into one of 69 different bins: > z$bins<-cut(z$x, breaks=c(-36:33), include.lowest=TRUE) > > Each bin is now 1 degree Celsius wide. Within each one, I calculate the > mean value of the corresponding fractional cropland data: > a<-tapply(z$y, z$bins, mean) > > Object 'a' now contains each bin category and the associated mean cropland > values, so 69 points in total. > > > Now, a problem arises when I try and plot these values using: > plot(a, xlab="Temperature", ylab="Fraction of Cropland", pch=20) > What happens is that R intuitively labels my x-axis from 1-70, which > corresponds to the bin factor values that were returned when the 'cut' > function was used. I would like to simply label the x-axis with my > temperature values, from -36 degrees to 33 degrees, instead of having > numbers 1-69. How can I do this?? > > Thanks, > > Jeremy Proville > M.Sc. Candidate > Bioresource Engineering, McGill University > -- View this message in context: http://www.nabble.com/Bin-Category-Labels-on-Axis-tp24042325p24074354.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.