[R] extracting the last row of each group in a data frame

[Peter Ehlers]

I would use pkg:plyr, but just to show how
versatile R is:

ind <- cumsum(rle(as.numeric(dat$Name))$lengths)
dat[ind, ]

where I'm assuming that your data frame is
called 'dat'.

  -Peter Ehlers

Hao Cen wrote:
> Hi,
> 
> I would like to extract the last row of each group in a data frame.
> 
> The data frame is as follows
> 
> Name Value
> A 1
> A 2
> A 3
> B 4
> B 8
> C 2
> D 3
> 
> I would like to get a data frame as
> Name Value
> A 3
> B 8
> C 2
> D 3
> 
> Thank you for your suggestions in advance
> 
> Jeff
> 
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