extracting the last row of each group in a data frame

Hi,

You could try plyr,

library(plyr)

ddply(d,.(Name), tail,1)

  Name Value
1    A     3
2    B     8
3    C     2
4    D     3

HTH,

baptiste

2009/11/16 Hao Cen <hcen at andrew.cmu.edu>:
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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extracting the last row of each group in a data frame

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