Unnecessary Whitespace around the plot

[therimalaya]

I am using the ggbiplot function while writing my thesis. I am having a lot of trouble with the unnecessary whitespace around the plot. sometime it is good, but not always. I tried using plot.margin on theme, but it did not worked. Is there any way, you can put some option on the plot, or can you guide me to remove the whitespace. All the other feature are very fine.

[Alyetama]

I know this is very old, but just in case someone else has the same question, you can do the following:

ggsave(my_img.png)
knitr::plot_crop(my_img.png)