Reset par to the default values at startup

Normally when I make my own plot functions, I make a construct :

op <- par("mypar"=myvalue)
on.exit(par(op))

which is the standard way of reverting the par to the previous values. Imagine you've been running some functions that did change some of the pars, and you need to reset to the default values at startup in R. What is the convenient way of doing so?

Or in other words : how does one reaches the default values for par()?

Every time a new device is opened par() will reset, so another option is simply do dev.off() and continue.

This is hacky, but:

resetPar <- function() {
    dev.new()
    op <- par(no.readonly = TRUE)
    dev.off()
    op
}

works after a fashion, but it does flash a new device on screen temporarily...

E.g.:

> par(mfrow = c(2,2)) ## some random par change
> par("mfrow")
[1] 2 2
> par(resetPar())     ## reset the pars to defaults
> par("mfrow")        ## back to default
[1] 1 1

From Quick-R

par()              # view current settings
opar <- par()      # make a copy of current settings
par(col.lab="red") # red x and y labels 
hist(mtcars$mpg)   # create a plot with these new settings 
par(opar)          # restore original settings

An alternative solution for preventing functions to change the user par. You can set the default parameters early on the function, so that the graphical parameters and layout will not be changed during the function execution. See ?on.exit for further details.

on.exit(layout(1))
opar<-par(no.readonly=TRUE)
on.exit(par(opar),add=TRUE,after=FALSE)

Use below script to get back to normal 1 plot:

par(mfrow = c(1,1))

dev.off() is the best function, but it clears also all plots. If you want to keep plots in your window, at the beginning save default par settings:

>def.par = par()

Then when you use your par functions you still have a backup of default par settings. Later on, after generating plots, finish with:

>par(def.par) #go back to default par settings

With this, you keep generated plots and reset par settings.