printing hash values in new line using tie - perl

Question

I have a hash with few keys and each key has 20 values.
%test={
a=> 10 14 34 56 ....
b=> 56 67 89 66 ...
..
}
#values= {a,b,..}
I want to tie values from this hash to another file as shown below
my input file.txt
ID
ID
ID
...
expected file.txt
ID ,10 ,56
ID ,14, 67
ID ,34, 89
ID ,56, 66
..
My code right now ties the all the values to the first line of my file. please help formatting it.
my $match = "ID";
tie my #lines, 'Tie::File', 'file.txt' or die "failed : $!";
for my $line (#lines) {
while ( $line =~ /^($match.*)/ ) {
$line = $1 . "," . join ',',#test{#values};
}
}
untie #lines;
right now my output is
file.txt
ID ,10 ,14, 34, 56,... 56, 67, 89, 66....
ID
ID
ID

Answer 1

I'm a bit confused by your question...
You have some template file that only contains ID at the beginning of (n) lines?
And you want to iterate over each $key by $test->{$key}[$line_count]?
Something seems fishy(I think you must be leaving something out) here. There's going to be quite a few ways to go wrong with this design...
Anyways, I think this is what you're going for:
my $match = "ID";
my $test = {
a => [ qw(1 3 5) ],
b => [ qw(2 4 6) ],
};
tie my #lines, 'Tie::File', 'file.txt' or die "failed : $!";
my $i = 0;
for my $line (#lines) {
if( $line =~ /^($match.*)/ ) {
my #stuff = ();
for my $key ( keys %$test ) {
push #stuff, $test->{$key}[$i];
}
$line = $1 . ", " . join(', ', #stuff);
$i++;
}
}
untie #lines;
Assuming that this is what you have/want:
$ cat file.txt
ID
ID
ID
$ test.pl
$ !cat
cat file.txt
ID, 1, 2
ID, 3, 4
ID, 5, 6

Answer 2

Do you simply want
my %test = (
a => [ 10, 14, 34, 56, ... ],
b => [ 56, 67, 89, 66, ... ],
);
for (0..$#{ $test{a} }) {
print(join(',', 'ID', $test{a}[$_], $test{b}[$_]), "\n");
}
You could write to a file instead of STDOUT by creating the file using
open(my $fh, '>', 'file.txt')
or die("Can't create file.txt: $!\n");
and then using
print($fh ...);
but it's better to let the user redirect the output to the file using >file.txt.

Answer 3

Here is my take, although the tie seems superfluous to me:
use strict;
use warnings;
use Tie::File;
my %test=(
a=> [qw(10 14 34 56)],
b=> [qw(56 67 89 66)]
);
my #values= qw(a b);
my $match = "ID";
tie my #lines, 'Tie::File', 'file.txt' or die "failed : $!";
my $i = 0;
for my $line (#lines) {
if ( $line =~ /^($match.*)/ ) {
$line = $1 . "," . join(',', map { $test{$_}->[$i]} #values );
$i++;
}
}
untie #lines;
Output (file.txt):
ID,10,56
ID,14,67
ID,34,89
ID,56,66