#postscript(family="Times", 'multi.ps', width=40)
#pdf(family="Times", 'multi.pdf', width=40)


# draw points (offsets is for color)
offsets   <- c(0.0, 0.3, 0.3, 0.6, 0.6)
linethick <- c(0.5, 0.5, 0.5, 1.5, 1.5)
leg.txt   <- c(
        "actual p(novel)", 
        "p'(novel), mehtod X",
        "p'(novel), method X+stdev", 
        "p'(novel), method X-fac",
        "p'(novel), method X-fac+stdev ")


#read source file
data_table <- read.table("multi.data", 
	col.names=c("vx1","vy1","vy2","vy3","vy4","vy5","vy6","vy7")) 

    #cbind() forms matrices by binding together matrices horizontally, 
    #or column-wise, and rbind() vertically, or row-wise
line1node <- cbind(data_table$vx1, data_table$vy1)
    #draw line1, xaxt="n" means not draw x axis now; 
    # lty=1 means solid line, lwd means line width
plot(line1node, 
    xaxt="n", yaxt="n", 
    xlab="Probability of novel symbol", 
    ylab="Number of symbol occurrences", 
    log = "x", 
    main="Figure multiple lines and custom ticks", 
    ylim=c(0.4,1), 
    type = "l", 
    col=gray(offsets[1]), 
    lty=1, lwd=linethick[1])

    # 1 means draw ticks on the bottom. At determines place making a tick
axis(1, at=c(1,2,3,4,5,6,7,8,9,10,20,30,40,50), font.axis=6 )
    # 2 means draw ticks on the left. 
axis(2, at=c(0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0) , font.axis=6 )

    #draw line 2. lty=3 means dotted
line2node <- cbind(data_table$vx1, data_table$vy2)
lines(line2node, type="l", col=gray(offsets[2]), lty=3, lwd=linethick[2]);

    # remove those rows if vy3 values above 1 and assign those
    # satisfied rows to line3smallnode
line3smallnode <- subset( data_table, !(vy3 > 1) )
    # draw line3. lty=2 means dashed
line3node <- cbind(line3smallnode$vx1, line3smallnode$vy3)
lines(line3node, type="l", col=gray(offsets[3]), lty=2, lwd=linethick[3]);

    # draw line4. lty=2 means dashed
line4node <- cbind(data_table$vx1, data_table$vy5)
lines(line4node, type="l", col=gray(offsets[4]), lty=1, lwd=linethick[4]);

    # draw line5. (lty=2 == lty="dashed")
lines(data_table$vx1, data_table$vy6, type="l", 
      col=gray(offsets[5]), lty="dashed", lwd=linethick[5]);

    # 10,0.7 is the position of legend. leg.txt is each line title. 
    # bty="n" remove the box around legend 
    # cex=0.9 means legend is 0.9 time of current font size
legend(10,0.7, leg.txt, lty = c(1,3,2,1,2), 
       col = gray(offsets),lwd=linethick, bty="n", cex = 0.9) 


#dev.off()  # This is only needed if you use pdf/postscript in interactive mode