[R] sorting a matrix by the column

markleeds at verizon.net markleeds at verizon.net
Wed Feb 11 07:18:16 CET 2009


this is a bad question but I can't figure it out and i've tried. if i 
sort the 2 column
matrix , temp1, by the first column, then things work as expected. But,
if I sort the 1 column matrix, temp2, then it gets turned coerced to a 
vector. I realize that I
need to use drop=FALSE but i've put it in a few different places with no 
success. Thanks.

temp1 <- matrix(rnorm(10),nc=2,nrow=5)
rownames(temp1) <- c("a","b","c","d","e")
print(temp2)
temp1 <- temp1[order(temp1[,1]),]
print(temp1)

temp2 <- matrix(rnorm(10),nc=1,nrow=5)
rownames(temp2) <- c("a","b","c","d","e","f","g","h","i")
print(temp2)
temp2 <- temp2[order(temp2[,1]),]   # PROBLEM IS HERE
print(temp2)




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