Save ggplot with a function

Question

I would like to create a function to save plots (from ggplot).

Here is a data frame:

### creating data frame
music <- c(\"Blues\", \"Hip-         


        

Answer 1

You can use print() to save plots produced from ggplot2 to a file.

First, define your function to save plots:

savePlot <- function(myPlot) {
        pdf("myPlot.pdf")
        print(myPlot)
        dev.off()
}

Create your plot:

 myPlot <- ggplot(ggplot(data=df.music, aes(x=music, y=number)) +
 geom_bar(stat="identity") +
 xlab(colnames(df.music)[1]) +
 ylab(colnames(df.music)[2]) +
 ylim(c(0,11)) +
 ggtitle("Ulubiony typ muzyki wśród studentów")

And finally call the function:

savePlot(myPlot)

---

Alternatively, you could just use ggsave() after creating your plot:

ggsave(filename="myPlot.pdf", plot=myPlot)

Answer 2

If you would like an image file instead of a pdf, also the following works

ggsave(filename="myPlot.jpg", plot=last_plot())

or with additional parameters, as follows.

ggsave(filename="myPlot.jpg", plot=lastplot(),
       width = 10, height = 5, 
       units = "cm", # other options are "in", "cm", "mm" 
       dpi = 200
       )

Also following file types are supported "eps", "ps", "tex" (pictex), "pdf", "jpeg", "tiff", "png", "bmp", "svg" or "wmf".

Answer 3

Following was useful for me, may be for someone else as well. One can save the last plot without explicitly referring it as well.

ggsave("filename.pdf",  # jpg, png, eps, tex, etc.
       plot = last_plot(), # or an explicit ggplot object name,
       width = 7, height = 5, 
       units = "in", # other options c("in", "cm", "mm"), 
       dpi = 300)