R/letter.it.R

In RSEIS: Seismic Time Series Analysis Tools

`letter.it` <-
function(a, corn=1)
  {
##X##
##X##    ###  put a letter in a figure
##X##    ###  a = one of 1-26 letters 
##X##    ###  corn = corner 1 2 3 4 = Low-Left UP-Left UP-Right Low-Right
    if(missing(corn)) { corn = 1 }
    letlabs=paste("(", letters,")", sep="")	     
    aa=letlabs[a]
    u=par("usr")
    oce=par("cex")
    par(cex=1.2)
    p1em=par('cin')
    shiftx= (u[2]-u[1])*0.02
    shifty=  (u[4]-u[3])*0.02 

    if(corn==1) {
                                        #	text(u[1]+shiftx*p1em[1],u[3]+shifty*p1em[2]   ,labels=aa,  adj=0)
      text(u[1]+shiftx,u[3]+shifty   ,labels=aa, adj=c(0 ,0.5), xpd=TRUE  )
    }
 
	if(corn==2) {
#	text(u[2]-shiftx*p1em[1],u[3]+shifty*p1em[2]   ,labels=aa,  adj=1)
	text(u[2]-shiftx,u[3]+shifty   ,labels=aa, adj=c(1, 0), xpd=TRUE )
	}

	if(corn==3) {
#	text(u[2]-shiftx*p1em[1],u[4]- shifty*p1em[2]  ,labels=aa,  adj=1)
        text(u[2]-shiftx,u[4]-shifty  ,labels=aa,  adj=c(1, 0.5), xpd=TRUE )
	}
	if(corn==4) {
#	text(u[1]+shiftx*p1em[1],u[4]- shifty*p1em[2] ,labels=aa,  adj=0)
	text(u[1]+shiftx,u[4]-shifty ,labels=aa,  adj=c(0 , 0.5 ), xpd=TRUE )
	}
	par(cex=oce)
}