# Custom Axes in R
# 16 March 2013
# NJG

##############################
default <- par(no.readonly=TRUE)

################################
# create random data with gamma distribution
x <- 1:20
y <- rgamma(20,1,2)

# set x limit to avoid clipping at start
par(mar=c(5,4,4,4))
plot(x,y,type="b",pch=23,bg="slateblue",
     xlim=c(0,20),ylim=c(0,1.3),
     axes=FALSE,ann=FALSE)

# use sequence and take default tick labels
axis(1,at=seq(0,20,by=5))

# use mtext to add text labels in the margins
mtext("Time",1,line=3)

# use sequence and override with user labels
axis(2, at=seq(0,1.3,length=4),labels=c("low","med","high","peak"),
     las=2)

# thicken up tick lines and move axis out a bit
axis(3,at=seq(0,20,by=5),line=1,lwd=2,lwd.ticks=2,font=2)

# move the axis and ticks inward with the mgp argument
axis(4,at=seq(0,1.3,length=4),labels=c("l","m","h","p"),
     las=2,mgp=c(0,1.4,1.9),tcl=2,
     col.axis="red",col="slateblue")

# overplot the axis to easily create minor tick marks
axis(4,at=seq(0,1.3,length=7),labels=FALSE,
     mgp=c(0,1.4,1.9),tcl=0.75,
     col="slateblue")


par(default)
rm(list=ls())