R devel - Oct 2005 - vector labels are not permuted properly in a call to sort() (R 2.1)

Not sure if this is the correct forum for this, but I've found what I  
would consider to be a potentially serious bug to the unsuspecting user.
Given a numeric vector V with class labels in R,  the following calls

1.
 > sort(as.matrix(V))

and

2.
 >as.matrix(sort(V))

produce different ouput. The vector is sorted properly in both cases,  
but only 2. produces the correct labeling of the vector. The call to  
1. produces a vector with incorrect labels (not sorted).

Code:
 >X<-c("A","B","C","D","E","F","G","H")
 >Y<-rev(1:8)
 >names(Y)<-X
 > Y
A B C D E F G H
8 7 6 5 4 3 2 1
 > sort(as.matrix(Y))
   [,1]
A    1
B    2
C    3
D    4
E    5
F    6
G    7
H    8
 > as.matrix(sort(Y))
   [,1]
H    1
G    2
F    3
E    4
D    5
C    6
B    7
A    8

Cheers,

The `problem' is that sort() does not doing anything special when given
a matrix: it only treat it as a vector.  After sorting, it copies
attributes of the original input to the output.  Since dimnames are
attributes, they get copied as is.

Try:
> y <- matrix(8:1, 4, 2, dimnames=list(LETTERS[1:4], NULL))
> y
  [,1] [,2]
A    8    4
B    7    3
C    6    2
D    5    1
> sort(y)
  [,1] [,2]
A    1    5
B    2    6
C    3    7
D    4    8

Notice the row names stay the same.  I'd argue that this is the correct
behavior.

Andy

> From: Greg Finak
> 
> Not sure if this is the correct forum for this, but I've 
> found what I  
> would consider to be a potentially serious bug to the 
> unsuspecting user.
> Given a numeric vector V with class labels in R,  the following calls
> 
> 1.
>  > sort(as.matrix(V))
> 
> and
> 
> 2.
>  >as.matrix(sort(V))
> 
> produce different ouput. The vector is sorted properly in 
> both cases,  
> but only 2. produces the correct labeling of the vector. The call to  
> 1. produces a vector with incorrect labels (not sorted).
> 
> Code:
> 
>X<-c("A","B","C","D","E","F","G","H")
>  >Y<-rev(1:8)
>  >names(Y)<-X
>  > Y
> A B C D E F G H
> 8 7 6 5 4 3 2 1
>  > sort(as.matrix(Y))
>    [,1]
> A    1
> B    2
> C    3
> D    4
> E    5
> F    6
> G    7
> H    8
>  > as.matrix(sort(Y))
>    [,1]
> H    1
> G    2
> F    3
> E    4
> D    5
> C    6
> B    7
> A    8
> 
> Cheers,
> 
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