R help - Sep 2008 - Extracting subsets by factor level?

Hi

I have a data frame which looks like the following (it is a table of commit logs
to a source repo). The Author column
is treated as a factor, by virtue of stringsAsFactors being set to TRUE, so I
can extract the number of commits
per author by using table(logs$Author).

Is there an elegant way to extract all subsets of this frame by the Author
column - i.e. that returns say a list of
data frames, each containing just the records for a specific value of Author?

Thanks
Rory
>head(logs)
  Revision Author                Date LinesChanged
1        6 user1  13/11/2007 15:41:53          488
2       11 user1 14/11/2007 09:04:43            3
3       12 user2 16/11/2007 12:26:04          522
4       13 user1 16/11/2007 12:27:55           90
5       14 user3 19/11/2007 09:32:54          159
6       15 user1 21/11/2007 13:38:41         1986



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Office: 36 St Andrew Square, Edinburgh EH2 2YB.
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Rory.WINSTON at rbs.com wrote:
> Hi
>
> I have a data frame which looks like the following (it is a table of commit
logs to a source repo). The Author column
> is treated as a factor, by virtue of stringsAsFactors being set to TRUE, so
I can extract the number of commits
> per author by using table(logs$Author).
>
> Is there an elegant way to extract all subsets of this frame by the Author
column - i.e. that returns say a list of
> data frames, each containing just the records for a specific value of
Author?
>   
Yup:

split(logs, logs$Author)
> Thanks
> Rory
>
>   
>> head(logs)
>>     
>
>   Revision Author                Date LinesChanged
> 1        6 user1  13/11/2007 15:41:53          488
> 2       11 user1 14/11/2007 09:04:43            3
> 3       12 user2 16/11/2007 12:26:04          522
> 4       13 user1 16/11/2007 12:27:55           90
> 5       14 user3 19/11/2007 09:32:54          159
> 6       15 user1 21/11/2007 13:38:41         1986
>
>
>
>
***********************************************************************************
> The Royal Bank of Scotland plc. Registered in Scotland No 90312. Registered
Office: 36 St Andrew Square, Edinburgh EH2 2YB.
> Authorised and regulated by the Financial Services Authority 
>
> This e-mail message is confidential and for use by the...{{dropped:20}}