[R] Automating plot labelling in custom function in lapply() ?

[Gavin Simpson]

Dear List,

Consider the following example:

dat <- data.frame(var1 = rnorm(100), var2 = rnorm(100),
                   var3 = rnorm(100), var4 = rnorm(100))
oldpar <- par(mfrow = c(2,2), no.readonly = TRUE)
invisible(lapply(dat,
                  function(x) {
                    plot(density(x),
                         main = deparse(substitute(x))) }
                  )
           )
par(oldpar)

I want to the main title in each of the density plots to be var1, var2, 
etc. The above code produces x[[1]], x[[2]] etc.

What do I need to modify to be able to use the name of x as the plot 
label within in the above situation?

Thanks in advance,

Gav
-- 
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Gavin Simpson                     [T] +44 (0)20 7679 5522
ENSIS Research Fellow             [F] +44 (0)20 7679 7565
ENSIS Ltd. & ECRC                 [E] gavin.simpsonATNOSPAMucl.ac.uk
UCL Department of Geography       [W] http://www.ucl.ac.uk/~ucfagls/cv/
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