[R] Data Grouping Question

[Chuck Cleland]

Here is a way, though probably not the best way:

table(apply(A, 1, function(x){paste(x, collapse="")}))

Kissell, Robert [EQRE] wrote:

> Hi,
> 
> I have a quick question regarding grouping data in R. I have the following matrix,
> 
> A =	0	1	1	0
> 	1	0	0	1
> 	1	0	0	1
> 	1	1	0	0
> 	1	0	0	1
> 	0	1	1	0
> 
> I would like to learn how I can group the data on unique rows of A and also count the number of times the row occurred. The command unique(A) provides a matrix with the unique rows, i.e., B
> 
> B =	0	1	1	0
> 	1	0	0	1
> 	1	1	0	0
> 
> but I am also interested in learning how I can count the number of unque rows too. The result can be in either one or two matrices, e.g.,
> 
> B =	0	1	1	0
> 	1	0	0	1
> 	1	1	0	0
> 
> Count =		1
> 		3
> 		2
> 
> or,
> 
> C =	0	1	1	0	1
> 	1	0	0	1	3
> 	1	1	0	0	2

-- 
Chuck Cleland, Ph.D.
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