I have a file foo.txt with this content:
chr1 15
chr11 5
chr11 8
chr1 7
chr2 23
chr1 35
I tried to sort it first according to the first column, and then according to the second column for breaking ties by the following command in linux shell:
sort -k 1,1 -k 2,2n foo.txt
But the result is stange:
chr1 7
chr1 15
chr11 5
chr11 8
chr1 35
chr2 23
What I expected was this:
chr1 7
chr1 15
chr1 35
chr11 5
chr11 8
chr2 23
EDIT
I checked the characters in file with od -fc foo.txt
as suggested in comments, there were no strange characters. Here is the result:
0000000 3.5274972e-09 8.7240555e-33 3.5274972e-09 8.716562e-33
c h r 1 \t 1 5 \n c h r 1 1 \t 5 \n
0000020 3.5274972e-09 8.8610065e-33 3.5274972e-09 2.5496164e+21
c h r 1 1 \t 8 \n c h r 1 \t 7 \n c
0000040 2.1479764e-33 2.5493397e+21 2.1359394e-33 9.37439e-40
h r 2 \t 2 3 \n c h r 1 \t 3 5 \n
0000057
I am using sort (GNU coreutils) 8.21
Any ideas?
od -c foo.txt