Script / sort question; sort on last field of a line?

[Chris F.A. Johnson]

On Fri, 5 May 2006, Peter wrote:

>
> On Thu, 4 May 2006, Chris F.A. Johnson wrote:
>
>> > >  sort -rk ... should do it
>> > 
>> >  This is by far the easiest solution posted, although I'm not sure why 
>> >  you
>> >  would need "-r". That reverses the sort order (i.e. to reverse 
>> >  alphabetic)
>> >  which wasn't in the problem description.
>> > 
>> >  Just to clarify Peter's answer. If you have N fields in a line, use:
>> > 
>> >     sort -k N
>>
>>    That doesn't help if you don't know how many fields there are,
>>    or if there is a variable number of fields.
>
> Oh, you mean he wants to sort variable length (in fields) lines ? There are 
> such algorythms. I think that they are called 'phone book sorting' or similar 
> (for obvious reasons). They are also used to sort f.ex. street names and 
> people names (which have titles e.g. Dr. Eng. Fr. etc prepended). One way to 
> do it with sort -k is to force the input to canonical length (in fields). 
> This can be the length, in fields, of the longest line (again in fields). 
> This requires two passes.

    Or there is the method I posted earlier:

awk '{ printf "%s\t%s\n", $NF, $0 }' | sort | cut -f2-

      Use $(NF-1) for penultimate field.


-- 
    Chris F.A. Johnson                      <http://cfaj.freeshell.org>
    ===================================================================
    Author:
    Shell Scripting Recipes: A Problem-Solution Approach (2005, Apress)
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