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rggplot2cairoggsave

Exporting images in R: Cairo and ggsave increasing specified dimensions

I'm trying to export a figure with dimensions 90x150 mm with 300 dpi using the ggsave() and Cairo(). The problem is that even though I correctly specified the figure dimensions on the code, they ended up far bigger then expected (281x468 mm). Here's the code I've been using:

x <- 1:10; y = x*x
plot = qplot(x, y, geom=c("point", "line"))

#ggsave
ggsave(plot, filename = "test.png", 
       width = 90, height = 150, dpi = 300, units = "mm", type = "cairo")

#Cairo
Cairo(90, 150, file="test2.png", type="png", bg="white", res = 300, units = "mm")
plot
dev.off()
Solution

  • Just figured out that Cairo() and ggsave() size output is affected by the image resolution, even if you choose a "metric" dimension as output.

    So basically, if you want a 90x150 figure at 300 dpi, you have to divide by 3 this dimensions (since 300 dpi is 3x the default resolution, 100dpi). Your setup then will be 30x50.