Eliminating duplicate entries in an array 1

[nfaber]

What is an easy way to eliminate duplicate entries in an array? I am reading a file in that has as many as 19 duplicate entries, and I want to eliminate all but one of course. Here is an excert form my script:

open (PFZ, $outemp) or die ("could not open pfizer.tmp: $!"
open (OUT, ">file.txt&quot or die ("could not open output file: $!"


# split the file and perform extraction logic.

foreach $var1 (<PFZ>) {

my @fields = split ( /\t/, $var1);

foreach (@fields) {
next if ( $fields[3] !~ /$query/ );
print (OUT &quot;$fields[17],$fields[3],$fields[13],$fields[5]\n&quot;
}
}


Any help is appriciated.

 

[danielhozac]

Well, if you place the file in an array called @file you could do the following:
my %entries;
foreach my $entry (@file)
{
$entries{$entry}++;
}
my @entries = keys (%entries); //Daniel

 

[nfaber]

Daniel,

I kinda a newbie here, but I do not see how that eliminates duplicate entries. Can you explain?

 

[MikeLacey]

%entries is a hash array - and keys to a hash array are two things, they can be a string (so they can store the values from an ordinary array) and they are unique.... Mike
michael.j.lacey@ntlworld.com
Email welcome if you're in a hurry or something -- but post in tek-tips as well please, and I will post my reply here as well.

 

[nfaber]

Oh I see! A hash must have unique keys so by writing the array to a hash the duplicates will be eliminated automatically. How clever!

 

[nfaber]

Mike,

How would you incorporate writing the array into a hash in the program show on my original post?