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rggplot2cairo

Cairo: Why does the Cairo not work in function?

My demo code was like that:

   p <- plot(c(1,3,4,5,6,4,3),c(1,2,3,4,5,6,7))
    myTiff <- function(p){
        tiff("E:/aaa.tiff")
        p
        dev.off()
    }
    myTiff(p)

But its does not work(the image was successfull saved, and the size was not 0 mb, but it cant open), whats wrong with it?

Solution

  • I think the problem is storing the plot in p. Try

    p <- data.frame(x=c(1,3,4,5,6,4,3), y=1:7)
myTiff <- function(p){
    tiff("E:/aaa.tiff")
    plot(p)
    dev.off()
}
myTiff(p)

    instead. In this case your function input are the points to be plottet not the stored plot.

    By using ggplot2 there are other ways since a ggplot can be stored:

    df <- data.frame(x=c(1,3,4,5,6,4,3), y=1:7)
p  <- ggplot(df, aes(x=x, y=y)) + geom_point()

myJpeg <- function(p){ 
  ggsave("E:/test.jpg", p) 
}