How to access the last value in a vector?

r dataframe vector
user14008 picture user14008 · Sep 16, 2008 · Viewed 347.4k times · Source

Suppose I have a vector that is nested in a dataframe one or two levels. Is there a quick and dirty way to access the last value, without using the length() function? Something ala PERL's $# special var?

So I would like something like:

dat$vec1$vec2[$#]

instead of

dat$vec1$vec2[length(dat$vec1$vec2)]

Answer

lindelof picture lindelof · Sep 17, 2008

I use the tail function:

tail(vector, n=1)

The nice thing with tail is that it works on dataframes too, unlike the x[length(x)] idiom.

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