[Rd] vector labels are not permuted properly in a call to sort() (R 2.1)

Greg Finak finak at mcb.mcgill.ca
Tue Oct 4 19:36:25 CEST 2005


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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