Reverse sort order of a multicolumn file in BASH

Question

I've the following file:

1 2 3 1 4 5 1 6 7 2 3 5 5 2 1 

and I want that the file be sorted for the second column but from the largest number (in this case 6) to the smallest. I've tried with

sort +1 -2 file.dat 

but it gives me the inversed order.

The results should be:

1 6 7 1 4 5 2 3 5 5 2 1 1 2 3 

Answer 1

sort -nrk 2,2 

does the trick.

n for numeric sorting, r for reverse order and k 2,2 for the second column.