I have done some more tinkering this morning. It seems it's the first polar plot that has the unusual size. If I add a third plot the last two grids match ok. So I added a further kludge to solve my problem, I added a dummy plot before the two 'real' plots and this works ok:
polar.plot(0,0,labels='',showgrid=FALSE) par(new=TRUE) While it works it's not very elegant. This could use some further investigation Darren Jim Lemon-2 wrote: > > On 10/08/2009 01:15 PM, darrenh65 wrote: >> Hi, >> I am attempting to create a polar chart (using plotrix polar.plt) and I >> need >> to colour a segment of the grid to indicate an area of interest, say from >> 90-120 degrees, for arguments sake. Is this possible? I can colour the >> whole >> grid by passing the grid.bg parameter through to radial.plot but I cannot >> find a way to colour a segment. >> >> thanks, >> Darren >> > Hi Darren, > You're right, there isn't any way to color just one sector of the > background in a polar.plot. That's the bad news. The slightly less bad > news is that I think you can kludge it by calling polar.plot twice with > par(new=TRUE) between. First do the plot without the sector, noting the > maximum extent of the grid ("maxlength" in the code). Then plot the > polygon by calling the function so: > > polar.plot(c(rep(maxlength,40)), > polar.pos=seq(start,end,length.out=40),rp.type="p",...) > par(new=TRUE) > > (you may want more than 40 points) Then plot your real data on top of > this. I can't test this right now, but will try it out in the next day > or so. > > Jim > > ______________________________________________ > 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. > > -- View this message in context: http://www.nabble.com/Colouring-a-grid-segment-tp25797407p25814366.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.