Sorting on Keys

[Porshe]

HI everyone...

I have a data file with about 9 fields in it. How can I make one field a key then get all the information about that record (the other 8 fields) in that record? I have to do a sort on one field then get all the other information from the remaining fields.

Thanks,
Porshe

 

[tsdragon]

You can build a hash using the one field as the key value, and either a string concatenating all the other fields as the value, or an anonymous array reference as the value. Then to sort by the keys just use:

foreach my $key (sort keys %hash) {
   #do something with the values here
}

Sorry if this answer is somewhat generic. If you can tell us what the data records look like, and what you need to do with them, we can be more help. Tracy Dryden
tracy@bydisn.com

Meddle not in the affairs of dragons,
For you are crunchy, and good with mustard.

 

[pkiller]

find a way of breaking (or accessing) your fields
individually. Then sort, search, whatever...

unix /etc/passwd contains 7 fields separated by ":"
to sort by 3rd field (user id):

perl -e '@a=<>; @b = sort {
@aa=split /:/,$a;
@bb=split /:/,$b;
$aa[2] <=> $bb[2] } @a; print @b' < /etc/passwd

to access information for uid == 0 (root):

perl -e 'while (<>) {
@aa = split /:/;
$aa[2] == 0 or next;
print; ## fields on @aa, original record on $_
last }' < /etc/passwd


regards

--
pkiller