Re: If Exists in an Array?

Note: untested. I think this is something that you might want to take a look at. Again, untested.

#!/usr/bin/perl

use strict;

my $logfile  = '/tmp/WDL_Scan_0000.csv';
my $locofile = '/tmp/locos.txt';

my ($locodn, $loco_data);
my ($linecnt1, $linecnt2) = 0;

open( my $file_1, '<', $logfile) 
  or die "Error: Cannot open $logfile.";
my @loco_data = <$file_1>;
close( $file_1 );

open( my $file_2, '<', $locofile) 
  or die "Error: Cannot open $locofile.";

while ( <$file_2> ) {
  chop($locodn);

  my ($RR_Name, $Loco_no, $Event_Date, $Event_Time,
    $Event_Code, $Event_Duration,$Source_File ) = split( /,/ );

  chop($loco_data);
  chop($Loco_no);

  $linecnt1++ if grep { /\b$Loco_no\b/ } @loco_data;
  $linecnt2++;

  print "Rec: ",$linecnt2, " In: ",$linecnt1, "\r";
}

close( $file_2 );
[download]

Comment on Re: If Exists in an Array? Download Code

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Re^2: If Exists in an Array? by 7stud (Deacon) on Nov 13, 2009 at 10:16 UTC
`my ($linecnt1, $linecnt2) = 0;` Is that what you meant to write? `linecnt1++ if grep { /\b$Loco_no\b/ } @loco_data;` Doing a hash lookup--like the op was trying to do--is more efficient than searching the entire array every time through the loop. You know, O(n squared) v. O(n) type stuff. use strict; use warnings; use 5.010; open (my $LOGFILE, "<", "logfile.txt"); open (my $MATCHFILE, "<", "matches.txt"); chomp(my @keys = <$MATCHFILE>); close $MATCHFILE; #Initialize hash: my %target_matches; @target_matches{@keys} = (); #now the keys exist, and the values are undef my($num_records, $match_count) = (0, 0); while (<$LOGFILE>) { chomp; my @fields = split /,/; if (exists $target_matches{$fields[1]}) { $match_count++; } $num_records++; say "Total records: $num_records, matches: $match_count"; } close $LOGFILE; [download] matches.txt: `1 2 3 4` [download] logfile.txt: `a,5,b,c,d,e a,2,b,c,d,e a,8,b,c,d,e a,3,b,c,d,e` [download] output: `Total records: 1, matches: 0 Total records: 2, matches: 1 Total records: 3, matches: 1 Total records: 4, matches: 2` [download]	[reply] [d/l] [select]
Re^3: If Exists in an Array? by keszler (Priest) on Nov 13, 2009 at 13:43 UTC
I prefer: `my %target_matches = map { chomp; $_,undef } <$MATCHFILE>;` [download] No need for @keys that way.	[reply] [d/l]
Re^3: If Exists in an Array? by 7stud (Deacon) on Nov 13, 2009 at 10:21 UTC
Note: untested. Ah.	[reply]
Re^3: If Exists in an Array? by batcater98 (Acolyte) on Nov 13, 2009 at 14:44 UTC
Thanks so much - this is going to work great. I have one other question. My source file just because of the way it is built - the $field1 value has leading spaces, how can I remove them on the fly? `Source Example: sx, 8849, sample1, source2 st, 893, sample2, source3 Matching Table: 8849 893` [download] With the leading white space the match does not hit. Thanks Again, Ad.	[reply] [d/l]
Re^4: If Exists in an Array? by keszler (Priest) on Nov 13, 2009 at 17:10 UTC
Assuming that your example pertains to this: `($RR_Name,$Loco_no,$Event_Date,$Event_Time,$Event_Code,$Event_Duration +,$Source_File)=split(/,/,$record);` [download] You're currently splitting on just the comma, so the spaces are retained. To lose the lead/trail spaces just change your split: `($RR_Name,$Loco_no,$Event_Date,$Event_Time,$Event_Code,$Event_Duration +,$Source_File)=split(/[ ,]+/,$record); # + ^ ^^` [download]	[reply] [d/l] [select]


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