I"m trying to plot with a png as background as this post : so I used this code
library(png)
#Replace the directory and file information with your info
ima <- readPNG("C:\\Documents and Settings\\Bill\\Data\\R\\Data\\Images\\sun.png")
#Set up the plot area
plot(1:2, type='n', main="Plotting Over an Image", xlab="x", ylab="y")
#Get the plot information so the image will fill the plot box, and draw it
lim <- par()
rasterImage(ima, lim$usr[1], lim$usr[3], lim$usr[2], lim$usr[4])
grid()
lines(c(1, 1.2, 1.4, 1.6, 1.8, 2.0), c(1, 1.3, 1.7, 1.6, 1.7, 1.0), type="b", lwd=5, col="white")
The issue is that I cannot find way to modify or to specify the width and height of the picture, in the display.
How to do this ?