[R] Some questione about plot

[Jim Lemon]

On 11/22/2010 10:14 PM, romzero wrote:
>
> Q1: How can i draw LSD (Least significant difference) on a plot?
> Like this...
> http://r.789695.n4.nabble.com/file/n3053430/LSD.jpg
>
> Q2: How can i draw the axis secondary scale?
>
Hi romzero,
This is somewhat of a guess, but:

segments(2.3,1.6,2.3,1.6+<value of LSD>)
text(2.2,1.6+<value of LSD>/2,"LSD(P<=0.05)",adj=1)

where <value of LSD> is the length of your line.
For the "secondary scale", I assume you mean the little ticks on the 
right side of the plot. Maybe:

plotlim<-par("usr")
par(xpd=TRUE)
segments(plotlim[2],<y values for ticks>,
  plotlim[2]+diff(plotlim[1:2])/50),<y values for ticks>)

where <y values for ticks> are the vertical positions for the ticks.

Jim