[R] sort matrix by sum of columns

[Albert Vilella]

Hi all,

I would like to know how can I sort the cols of a matrix by the sum of
their elements.


a <- matrix(as.integer(rnorm(25,4,2)),10,5)
colnames(a) = c("alfa","bravo","charlie","delta","echo")

I guess I should use colSums, and then rearrange the matrix somehow
according to the result.

My idea is to display a "sorted" barplot:

barplot(a, horiz=TRUE, legend.text=T)

Thanks in advance,

    Albert.