[R] Changing ungrouped cases to grouped cases

[David L Carlson]

> dtf <- read.table(text="y     A   B   C
+ 0     1    1   2
+ 0     1    2   1
+ 1     1    1   2
+ 0     1    1   2
+ 1     1    1   2
+ 1     1    2   1
+ 0     1    2   2",
+ header=TRUE)
> dtagroup <- aggregate(y~A+B+C, dtf, sum)
# Gets you the groups. If you need the column/row order:

> dtagroup <- dtagroup[order(dtagroup$y, decreasing=TRUE),c(4, 1:3)]

----------------------------------------------
David L Carlson
Associate Professor of Anthropology
Texas A&M University
College Station, TX 77843-4352

> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Christopher Desjardins
> Sent: Thursday, July 19, 2012 7:35 PM
> To: R help
> Subject: [R] Changing ungrouped cases to grouped cases
> 
> Hi,
> I have my data the following way:
> 
> y     A   B   C
> 0     1    1   2
> 0     1    2   1
> 1     1    1   2
> 0     1    1   2
> 1     1    1   2
> 1     1    2   1
> 0     1    2   2
> .
> .
> .
> And so on.  How can I make my data look like the following:
> y   A  B  C
> 2   1   1  2
> 1   1   2  1
> 0   1   2   2
> .
> .
> .
> 
> In other words how can I change my ungrouped cases into grouped cases?
> Thanks!
> Chris
> 
> 	[[alternative HTML version deleted]]
> 
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