Re: problem with command sort after uniq -c

[Philip Rowlands]

On Mon, 10 Mar 2008, Damien ANCELIN wrote:

> I met a problem with the sort command : I've used the uniq command with the -c 
> option to count some numbers, and then applying sort -n don't sort lines by 
> numeric order of the first field.
> Here is an example (my sort version is 5.97) :
> $ cat bug_sort | sort -n
>   1320 51970
>   1692 12345
>  22681 8060
>  26063 8649
>   2668 33603
>   3487 44496
>   4350 23246
>  47013 8000
>  5447 20000
> 81724 5000

You don't say which locale your environment is configured to use for 
sorting, but I'd bet it's one which treats whitespace differently to how 
you expect.

> With only spaces between the 2 fields, sort -n read 1 number per line 
> and use it to do the sort : 2668 33603 is read as 266833603. With this 
> consideration, the result of sort is correct, but it's not what I 
> expected (and I didn't see this behaviour in the documentation).

The command "sort -n" treats the whole line as the sort key. Specifying 
"sort -k1,1n" will use just the first field, in ascending numerical 
order.


Cheers,
Phil