not getting sort output in awk - awk

Question

I am using book "The AWK programming langauge" by Aho ,Kernighan ..
On page 20 they have given a program which doesn't work on my system.
emp.data is
Beth 4.00 0
Dan 3.75 0
Kathy 4.00 10
Mark 5.00 20
Mary 5.50 22
Susie 4.25 18
program they have given is
awk '{ printf("%6.2f %s\n" , $2*$3, $0) }' emp.data | sort
and the output they have given is
But my output is
0.00 Beth 4.00 0
0.00 Dan 3.75 0
100.00 Mark 5.00 20
121.00 Mary 5.50 22
40.00 Kathy 4.00 10
76.50 Susie 4.25 18
so whats happening ?

Answer 1

Your awk is broken or you have control chars in your input.
Your printf syntax is wrong (but would still produce correct output)
To get "2" out of the way: printf is a builtin language construct, not a function. When you do this:
printf("%s",foo)
you are not calling a printf function with 2 arguments, you are invoking the printf builtin with 1 argument which you are constructing from "(" "%s" "," "foo" and ")". The correct syntax is simply:
printf "%s",foo
but you can stick brackets around any of that and it won't add any value but won't break it either. Any of these would "work" in the same way:
printf ("%s"),foo
printf "%s",(foo)
printf ("%s"),(foo)
printf (((((((((("%s",foo))))))))))
More importantly, though is point "1" above: you're telling awk to produce output formatted as:
"%6.2f ...."
which means that the leading digits should be padded with up to 2 leading spaces on the left but your output has no leading spaces on the first line. That is impacting your "sort" but there's more going on here too since given the strings:
2
10
it doesn't matter if you do a numeric sort or an alphabetic sort because 2 is numerically less than 10 but space is also numerically less than 1 so the result should be the same either way.
Your posted output, though, is implying that your sort is sorting alphabetically in such a way that "100" is less than " 40" which just is not the way sort works. Even if somehow in your locale was greater than "1" alphabetically, it wouldn't explain why you get the equivalent of:
2
10
3
in your output, i.e. sometimes it treats space as less than one and other times as more.
Since your awk is clearly producing bad output there is definitely a problem with either your awk or your input file, so I think it's unlikely that there's also a problem with your sort tool.
Try these commands and post your result if you'd like help debugging your problem:
$ awk '{ printf "%6.2f\n" , $2*$3 }' emp.data
0.00
0.00
40.00
100.00
121.00
76.50
$ awk '{ printf "%6.2f\n" , $2*$3 }' emp.data | sort
0.00
0.00
40.00
76.50
100.00
121.00
I had one other thought - if you messed up the copy/paste of your awk output then maybe it's a locale issue. Try doing this:
export LC_ALL=C
and then running the command again (without the "-n" on sort).

Answer 2

Try sort -n at the end, to do a numerical sort. The default sort would put 10 before 2.

Answer 3

They have assumed sort sorts numerically, your sort appears to default to alphabetically.
Have a look at your sort command line options to see if you can make it numeric.