in reply to comparing lists

Compared with file I/O manipulating hashes is cheap. Something like this perhaps: 

use warnings;
use strict;

open inFile, '<', "accts_to_exclude.txt" || die "Cannot open accts_to_
+exclude.txt";
my %excludeList = map {chomp; $_ => undef} <inFile>;
close inFile;

open inFile, '<', "list1.txt" || die "Cannot open list1.txt";
my %acctList = map {chomp; $_ => undef} <inFile>;
close inFile;

open inFile, '<', "list2.txt" || die "Cannot open list2.txt";
my %diffList = map {chomp; $_ => undef} <inFile>;
close inFile;

open inFile, '<', "list3.txt" || die "Cannot open list3.txt";
my %nameList = map {chomp; $_ => undef} <inFile>;
close inFile;

open orgAcctList, '<', "orig_accts.txt" || die "Cannot open orig_accts
+.txt";
open outFile, '>', 'output.txt' || die "Cannot open output file output
+.txt";

while (my $line = <orgAcctList>){
    chomp $line;
    my ($filename, $state, $amt, $ttl, $account, $name, $invnum) = spl
+it /\t/, $line;
    next if exists $excludeList{$account};
    print outFile "$filename $state $amt $ttl $account $name $invnum\n
+";
    
    if (defined $acctList{$account}) {
        # do something (write this info to file1)
        next;
    }
    
    if (defined $diffList{$account}) {
        # do something (write this info to file2¡K)
        next;
    }
    
    if (defined $nameList{$name}) {
        # do something (write this info to file2)
        last;
    }
}

[download]
DWIM is Perl's answer to Gödel

Replies are listed 'Best First'.
Re^2: comparing lists
by Anonymous Monk on Feb 04, 2006 at 04:02 UTC
    Thank you both for your response. Graff, your tool is indeed very helpful for a lot of what we do. For this solution though, Grandfather's solution does seem a bit more relevant and as I am somewhat under time constraints to complete this script, it seemed more logical as I can add on to my existing code.
    I've made some slight changes to the code above ...but after spending numerous hours debugging the script, I still can't seem to get it work properly. I maybe missing some logic here...but when I run the script, it seems to output everything into nc_load.txt

    Here's the code: 
    #!/usr/bin/perl -w
$excludeaccts = "accts_to_exclude.txt";
open(EXCLUDELIST, $excludeaccts) || die ("Cannot open $excludeaccts");
#Load accounts-to-exclude into a hash table
%exclusionlist = map {chomp; $_ => undef} <EXCLUDELIST>;
close(EXCLUDELIST);

$ncaccts = "nc_acct_list.txt";
open(NCLIST, $ncaccts) || die ("Cannot open $ncaccts");
%ncacctlist =  map {chomp; $_ => undef} <NCLIST>;
close(NCLIST);

$ccaccts = "cc_acct_list.txt";
open(CCLIST, $ccaccts) || die ("Cannot open $ccaccts");
%ccacctlist = map {chomp; $_ => undef} <CCLIST>;
close(CCLIST);

$ccnames = "cc_name_list.txt";
open(CCNALIST, $ccnames) || die ("Cannot open $ccnames");
%ccnamelist = map {chomp; $_ => undef} <CCNALIST>;
close(CCNALIST);

$origaccts = "orig_accts_list.out";
open(ORIGACCTLIST, $origaccts) || die ("Cannot open $origaccts");

open($output, '>', 'output.txt' || die "Cannot open output file output
+.txt");

open($ncoutput, '>','nc_load.txt' || "Cannot open output file nc_load.
+txt");
open($ccoutput, '>', 'cc_load.txt' || "Cannot open output file cc_load
+.txt");

while ($line = <ORIGACCTLIST>){
chomp $line;
($filename, $state, $amt, $ttl, $account, $name, $invnum) = split /\t/
+, $line;
next if exists $exclusionlist{$account};
print $output "$filename\t$state\t$amt\t$ttl\t$account\t$name\t$invnum
+\n";


if (defined $ncacctlist{$account}) {
        print $ncoutput "$filename\n";
        next;
    }

if (defined $ccacctlist{$account}) {
        print $ccoutput "$filename\n";
        next;
    }

if (defined $ccnamelist{$name}) {
        print $ccoutput "$filename\n";
        last;
    }
        print $ncoutput "$filename\n";
###(I added the above line such that anything that's not in $nccctlist
+, $ccacctlist, $ccnamelist will be printed to nc_load.txt file If I r
+un it without this line, nothing is being printed to nc_load.txt or c
+c_load.txt)###
}

    [download]

    Any suggestions as to what I maybe doing wrong here? Thanks.
[reply]
[d/l]

      I see you are using if (defined $xxx{$yyy}) where you probably intended if (exists $xxx{$yyy})

      In general it is useful to provide the fail reason for opens using $!:

      open(NCLIST, $ncaccts) || die ("Cannot open $ncaccts: $!");

      [download]

      The line open($output, '>', 'output.txt' || die "Cannot open output file output.txt"); has a missing ) and (. It should be open($output, '>', 'output.txt') || die ("Cannot open output file output.txt: $!");

      You should always use the three parameter open. It makes the input explicit and in other contexts where the file name is provided by the user avoids malicious effects from a user putting > at the start of a file name.

      DWIM is Perl's answer to Gödel
[reply]
[d/l]
[select]
        Thanks a lot! That cleared up many things. I had to make one other slight modification...in the while loop, I cannot use LAST, rather I want to use NEXT at the end also because I want to continue to check until the end of the file rather than break the loop as soon as the last requirement is met. 

        while ($line = <ORIGACCTLIST>){
chomp $line;
($filename, $state, $amt, $ttl, $account, $name, $invnum) = split /\t/
+, $line;
$name =~ s/\s+$//g;
next if exists $exclusionlist{$account};
print $output "$filename\t$state\t$amt\t$ttl\t$account\t$name\t$invnum
+\n";


if (exists $ncacctlist{$account}) {
        print $ncoutput "$filename\n";
        next;
    }

if (exists $ccacctlist{$account}) {
        print $ccoutput "$filename\n";
        next;
    }

if (exists $ccnamelist{$name}) {
        print $ccoutput "$filename\n";
        next;
    }
        print $ncoutput "$filename\n";
        next;
}

        [download]
[reply]
[d/l]

In Section Seekers of Perl Wisdom