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# 15  
Old 08-14-2007
Quote:
Originally Posted by matrixmadhan
Look at this output !
Code:
echo "21237890" | awk '{ print substr($0, 0, 4) }'
2123

echo "21237890" | awk '{ print substr($0, 1, 4) }'
2123

Though the index starts at 1, there isn't any problem if ' 0 ' is used as it would default to ' 1 '.

and for the date format.

OP had specified that the input file would contain date value of the form YYYYMMDD
then what is the need to explicitly specify the format specifier when we are sure that we are going to extract ' 4 ' digit - ' 2 ' digit - ' 2 ' digit
Smilie

I don't really find the need for that.
matrixmadhan,

With your solution I get an output as:

Code:
199-1-1,US,"2"
200-3-3,AU,"w"

instead of:

Code:
1990-01-01,US,"2"
2001-03-03,AU,"w"

and that's not in the form YYYY-MM-DD Smilie

Regards
# 16  
Old 08-14-2007
surprising !

I get the following output

Code:
cat  3
date|country|ticker
19990101|US|2
20010303|AU|w

Code:
awk -F"|" '{ if ( NR == 1 ) { print } else { printf "%d-%d-%d,%s,\"%s\"\n", substr($1, 0, 4), substr($1,5,2), substr($1,7,2), $2, $3 } }' 3
date|country|ticker
1999-1-1,US,"2"
2001-3-3,AU,"w"

But I accept that printf format specifier should be used as

printf "%04d-%02d-%02d
# 17  
Old 08-14-2007
matrixmadhan,

Maybe you're right but I can't explain it, with:

Code:
echo "19990101"|awk '{print substr($0, 0, 4)}'

I get as output:

Code:
199

It don't work properly if I start the substring with 0.
I'm working home with awk version 1.2 (Dec 22 1994) on a Linux box (Debian Etch), I'll try it tomorrow on a HP machine.

Thanks and best regards
# 18  
Old 08-14-2007
Code:
$ echo "19990101"|awk '{print substr($0, 0, 4)}'
1999
$ echo "19990101"|awk '{print substr($0, 1, 4)}'
1999

I guess some awk's are more 'permissive' than others - try it with '1'
# 19  
Old 08-14-2007
Quote:
Originally Posted by vgersh99
Code:
$ echo "19990101"|awk '{print substr($0, 0, 4)}'
1999
$ echo "19990101"|awk '{print substr($0, 1, 4)}'
1999

I guess some awk's are more 'permissive' than others - try it with '1'
Ok, I'm confinced and 1 works properly, though in that case, it's for reason of compatabilty better to start with 1, which is used in a lots of tutorials and books.

Regards
# 20  
Old 08-15-2007
hi, try this one
For AWK you can try follow:
Code:
sed 's/|/,/g' filename | awk 'BEGIN{FS=","}
{
if (NR==1)
print $0
else
{
printf("%s-%s-%s,%s,\"%s\"\n",substr($1,1,4),substr($1,5,2),substr($1,7,2),$2,$3)
}
}'

For SED you can try follow:
Code:
sed  -e 's/\([0-9][0-9][0-9][0-9]\)\([0-9][0-9]\)\([0-9][0-9]\)/\1-\2-\3/' 
       -e '2,$s/\([a-zA-Z0-9]\)$/"\1"/' 
      -e 's/|/,/g' 
filename

Last edited by summer_cherry; 08-15-2007 at 06:11 AM..
# 21  
Old 08-15-2007
Next time i might try nawk and use some of your (this means all of you) suggestions. Thank you.
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