How to resize and save plots in png format?

Question

I would like to plot the results from a quantile regression, but am not able to:

1. control the dimensions/size of the plots and
2. save the plots as png.

Here is my code:

require(quantreg) data(engel) attach(engel) xx <- income - mean(income) zz <- c(120, diff(income)) fit1 <- summary(rq(foodexp~xx+zz, tau=2:98/100)) 

Then:

png('res.png') plot(fit1, mfrow=c(1,2)) 

Only the zz plot is saved to the res.png file.. Is there any way I can save the plots in separate files (two and one)? and how do I control the width/height of the plots? I like all the individual plots to have width=height (square) when i save them to the .png file?

Answer 1

You can control the image dimensions by png argument.

png("image.png", width = 800, height = 600) plot(...) dev.off() 

To "finish" the image, use dev.off.