[R] Sorting Dataframes

[Dennis Murphy]

Hi:

Here's another approach using the plyr package:

# Write a function that takes a data frame as input and outputs a data frame
f <- function(df) df[which.max(df$Fish), ]
ddply(x, 'Bin', f)
  Bin Depth Fish
1   1     8   24
2   2     8   21
3   3    12   33

HTH,
Dennis

On Tue, Jun 7, 2011 at 3:32 PM, SamiC <s.cox.10 at aberdeen.ac.uk> wrote:
> So I have figured out how to do it via a series of loops and conditions, but
> i am thinking there must be a quicker way to do it.
>
> an example.
>
> Bin     Depth   Fish          to:      Bin   Depth        MaxFish
> 1          4         2                       1      8               24
> 1          8         24                     2      8               21
> 1          12        4                     3      12              33
> 2          4         3
> 2           8        21
> 2           12       2
> 3           4        12
> 3            8       2
> 3            12      33
>
> --
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