all x axis labels are not displaying in 45 degree - r

Question

I'm having the code as like below. But I'm not getting all the x axis labels and it is not displaying in 45 degree when I try to have this in pdf. Since I'm new, Please help me correct this option.
pdf(file="figure.pdf", height=3.5, width=5, onefile=TRUE)
Runtime <- c(579,0,581,610,830,828,592,651,596,596,591,581,587,594,604,606,447,434,445)
Runtime
g_range <- range(0,Runtime)
g_range
plot(Runtime, type="o", col="blue", ylim=g_range,axes=FALSE, ann=FALSE)
lab=c('2011-07-20','2011-08-03','2011-08-10','2011-08-17','2011-08-24','2011-08-25','2011-08-27','2011-08-31','2011-09-07','2011-09-10','2011-09-14','2011-09-21','2011-09-28','2011-10-05','2011-10-06','2011-10-07','2011-10-13','2011-10-19','2011-10-31')
box()
lab
axis(1, at=1:19, lab=F)
text(axTicks(1), par("usr")[3] - 2, srt=45, adj=1, labels=lab, xpd=T, cex=0.8)
axis(2, las=1, at=500*0:g_range[2])
title(main="Runtime", col.main="red", font.main=4)
title(xlab="Build", col.lab=rgb(0,0.5,0))
title(ylab="MS", col.lab=rgb(0,0.5,0))
legend(1, g_range[2], c("AveElapsedTime"), cex=0.8, col=c("blue"), pch=21, lty=1);
dev.off()

Answer 1

When I run your code, I do not get the image you show. The problem is this line:
text(axTicks(1), par("usr")[3] - 2, srt=45, adj=1, labels=lab, xpd=T, cex=0.8)
as axTicks(1) returns:
> axTicks(1)
[1] 5 10 15
So what is happening is that your 19 labels are being plotted at those 3 locations.
If you want to plot at the locations of the ticks (1:19) then:
text(1:19, par("usr")[3] - 2, srt=45, adj=1, labels=lab, xpd=T, cex=0.8)
will work.
Here is a full example based on your code.
Runtime <- c(579,0,581,610,830,828,592,651,596,596,591,581,587,
594,604,606,447,434,445)
g_range <- range(0,Runtime)
lab <- c('2011-07-20','2011-08-03','2011-08-10','2011-08-17','2011-08-24',
'2011-08-25','2011-08-27','2011-08-31','2011-09-07','2011-09-10',
'2011-09-14','2011-09-21','2011-09-28','2011-10-05','2011-10-06',
'2011-10-07','2011-10-13','2011-10-19','2011-10-31')
## plot
op <- par(mar = c(6,4,4,2) + 0.1) ## bigger bottom margin
plot(Runtime, type="o", col="blue", ylim=g_range, axes=FALSE, ann=FALSE)
box()
axis(1, at=1:19, lab=FALSE)
text(1:19, par("usr")[3] - 40, srt=45, adj=1.2, labels=lab, xpd=T, cex=0.7)
axis(2, las=1, at=500*0:g_range[2])
title(main="Runtime", col.main="red", font.main=4)
title(xlab="Build", col.lab=rgb(0,0.5,0), line = 4.5)
title(ylab="MS", col.lab=rgb(0,0.5,0))
legend("topright", c("AveElapsedTime"), cex=0.8, col=c("blue"), pch=21, lty=1)
## reset par
par(op)
This might be better handled using function in the gridBase package though, which allows grid and base graphics to intermingle. The reason I say it might be better is that you can specify that the y coordinate be set in terms of numbers of lines rather that trying to work out a suitable value for y in terms of the plotted data.
Here is an example:
## load gridBase
require(gridBase)
## do the base plot parts
op <- par(mar = c(6,4,4,2) + 0.1) ## bigger bottom margin
plot(1:19, Runtime, type="o", col="blue", ylim=g_range, axes=FALSE, ann=FALSE)
box()
axis(1, at=1:19, lab=FALSE)
axis(2, las=1, at=500*0:g_range[2])
title(main="Runtime", col.main="red", font.main=4)
title(xlab="Build", col.lab=rgb(0,0.5,0), line = 4.5)
title(ylab="MS", col.lab=rgb(0,0.5,0))
legend("topright", c("AveElapsedTime"), cex=0.8, col=c("blue"), pch=21, lty=1)
## at this point, DO NOT alter the dimensions of the plotting window
## now do the grid business
vps <- baseViewports()
pushViewport(vps$inner, vps$figure, vps$plot)
## this adds the text
grid.text(lab, x = unit(1:19, "native"), y = unit(-1, "lines"),
just = "right", rot = 60, gp = gpar(cex = 0.7))
## this finishes off the viewport - you have to do this or things will go wrong:
popViewport(3)
## reset par
par(op)
Note this can be a bit picky on screen, rerunning the gridBase example on my R 2.13.2 install doesn't produce any labels. Closing the device and then running the code afresh works though. I don't think this should be a problem if you are drawing to a pdf() device.