perl to merge csv files removing the headings - perl

Question

I have several monthly reports in csv format in a folder. The csv files all have 8 common columns (with headings) . Using perl, I would like to merge these files together line by line.
say
file 1:
1,2,3,4,5,6,7,8,
a1,b1,c1,d1,e1,f1,g1,h1,
a1,b1,c1,d1,e1,f1,g1,h1,
a1,b1,c1,d1,e1,f1,g1,h1,
file 2:
1,2,3,4,5,6,7,8,
a2,b2,c2,d2,e2,f2,g2,h2,
a2,b2,c2,d2,e2,f2,g2,h2,
a2,b2,c2,d2,e2,f2,g2,h2,
I would like the output to look something like that (join the rows and remove the headings)
output:
1,2,3,4,5,6,7,8,
a1,b1,c1,d1,e1,f1,g1,h1,
a1,b1,c1,d1,e1,f1,g1,h1,
a1,b1,c1,d1,e1,f1,g1,h1,
a2,b2,c2,d2,e2,f2,g2,h2,
a2,b2,c2,d2,e2,f2,g2,h2,
a2,b2,c2,d2,e2,f2,g2,h2,
I have managed to save the names of the files in an array. but for some reason, I could not join them.
can you please help me figure out what is wrong with my code. I am quite new to perl.
#! C:Strawberry/perl/bin;
use feature ':5.12';
use strict;
use warnings;
my $data_directory = 'R:/testing_data/';
opendir( DIR, $data_directory ) or die "Could not open $data_directory $!\n";
my #files = grep {/_monthlyreport\.csv$/} readdir(DIR); #to get on the monthly reports csv files
foreach my $file (#files) {
open( HANR, "<", '$data_directory' . my $files ) or die "cannot open $files: $!"; #read handler
open( HANW, ">>", "G:/outputfile_script.csv" ) or die "error $! \n"; #write handler for creating new sorted files
my #lines = ();
#lines = <HANR>;
foreach my $line (#lines) {
chomp($line);
my $count++;
next unless $count; # skip header i.e the first line containing stock details
print HANW join $line, "\n";
}
my $count = -1;
close(HANW);
close(HANR);
}
closedir(DIR);
exit 0;

Answer 1

Your open statement to your input filehandle is malformed, and my $count++; is also broken.
I'd also recommend modernizing your code by using lexical file handles. The following is a cleaned up version of your code:
use feature ':5.12';
use strict;
use warnings;
use autodie;
my $data_directory = 'R:/testing_data/';
opendir my $dh, "$data_directory";
open my $outfh, ">>", "G:/outputfile_script.csv";
my $seenheader = 0;
while (my $file = readdir $dh) {
next unless $file =~ /_monthlyreport\.csv$/;
open my $infh, '<', "$data_directory/$file";
while (<$infh>) {
print $outfh $_ if $. > 1 || ! $seenheader++;
}
}

Answer 2

This line is wrong.
open(HANR ,"<",'$data_directory'.my $files) or die "cannot open $files: $!";
Should be
open(HANR ,"<","$data_directory".$files) or die "cannot open $files: $!";

Answer 3

Add a counter and stop printing if the counter equals 0;
#! C:Strawberry/perl/bin;
use feature ':5.12';
use strict;
use warnings;
my $data_directory = 'R:/testing_data/';
opendir(DIR,$data_directory) or die "Could not open $data_directory $!\n";
my #files = grep {/_monthlyreport\.csv$/} readdir(DIR); #to get on the monthly reports csv files
foreach my $file (#files) {
open(HANR ,"<",'$data_directory'.my $files) or die "cannot open $files: $!"; #read handler
open(HANW , ">>","G:/outputfile_script.csv") or die "error $! \n"; #write handler for creating new sorted files
my #lines=();
#lines=<HANR>;
my $i =0;
foreach my $line (#lines){
next if ($i==0) ;
chomp ($line) ;
my $count++;
next unless $count; # skip header i.e the first line containing stock details
print HANW join $line,"\n";
}
my $count= -1;
close(HANW);
close(HANR);
}
closedir(DIR);
exit 0;