Logical issue in Perl numerically iterating over 10 directories and populating them with numbers? - perl

Question

My basic goal is to take the integers 1 to 100,
and split them into 10 parts, where the initial part is integers 1 to 10,
and the next part is 11 to 20, each part having 10 numbers each.
I want the first part to go into the directory NUMBERS_1
containing the numbers 1 to 10 in a file called FILE_1.txt
and the next part to go into directory NUMBERS_2
containing the numbers 11 to 20 in a text file: FILE_2.txt
and so forth.
How I approached this problem was that I initialized an array with 100 numbers,
and then created an array reference by destructively splicing the array into 10 parts composed of no more than 10 integers each.
Then I created 10 folders NUMBERS_1 to NUMBERS_10 on a for-loop.
As I was doing this for-loop, I created a directory list of all the directories I created.
Then some problem is occuring as I iterate over the directories.
So I attempted to iterate over the directories in a foreach loop,
and then I try to open each of the directories in this directory list one at a time,
create a text file, fill it with a quantity of ten integers, close the file, and then close the directory. It doesn't seem like I'm opening the directories, but I'm not getting any error messages, and I have multiple open or die statements so shouldn't I be getting some errors?
ISSUE:
My problem is that my 10 text files are being created in my current working directory, not on each in the 10 directories that I created, but I just can't see the error in my logic.
#!/usr/bin/env perl
# The objective of this program is to an array of 100 numbers in 10 parts
# And write each 10 parts into 10 files with ten numbers each.
use strict;
use warnings;
use feature 'say';
my #numbers = (1 .. 100);
my $partition_size = 10;
my #number_groups = ();
my $num_elements;
my #directories;
my $directory_handle;
my $incrementer; # Incrementing over the directories ... not the same as my use of $i
my $i;
# This right here is very powerful
# I must confess that I received some help from zdim at stackoverflow:
# https://stackoverflow.com/questions/45158306/splitting-an-array-into-n-accessible-parts-within-perl
# splice is destructive so numbers will be empty,
# but at that cost the array reference #number_groups will have 10 sections filled with 10 numbers each from 1 to 100
push #number_groups, [splice(#numbers, 0, $partition_size)] while #numbers;
$num_elements = scalar(#number_groups); # Retrieiving size of array reference.
# Why is it not being treated like an array reference, but like an array?;
# Here I'm saying every item of the array reference #number_groups.
say "Let's take a look at this array reference containing each of the pieces of numbers 1 to 100";
say "#$_\n" for #number_groups;
# Now let's make folders containing the numbers 1 to 100, with 10 numbers in each folder.
# And the folders properly labeled.
say "I will now create $num_elements folders";
for(my $i = 1; $i <= $num_elements; $i++)
{
mkdir "NUMBERS_$i" or warn "Could not create folder $_, probably because it already exists";
push #directories, "NUMBERS_$i";
}
# I know that the script is misbehaving somewhere below this line.
$incrementer = 0; # The incrementer is at zero because the first item in the list of directories is the zero-ith item.
$i = 1; # This incrementer "$i" is for the 10 logical slices of the numbers from 1 to 100
foreach(#directories)
{
opendir($directory_handle, $_) or die "Could not open directory $_";
my $file = "FILE_$i.txt"; my $filehandle;
say "\nThe incrementer is at $i in directory $_";
open($filehandle, '>', $file) or die "Could not open file $_";
while(my $line = <$filehandle>)
{
chomp $line;
foreach(#{$number_groups[$incrementer]}){print "$_\t";}
}
close $filehandle or die "Could not close file $_";
closedir($directory_handle) or die "Could not close directory $_";
$incrementer++;
$i++;
}
Running this script produces the following output:
Let's take a look at this array reference containing each of the pieces of numbers 1 to 100
1 2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30
31 32 33 34 35 36 37 38 39 40
41 42 43 44 45 46 47 48 49 50
51 52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68 69 70
71 72 73 74 75 76 77 78 79 80
81 82 83 84 85 86 87 88 89 90
91 92 93 94 95 96 97 98 99 100
I will now create 10 folders
The incrementer is at 1 in directory NUMBERS_1
1 2 3 4 5 6 7 8 9 10
The incrementer is at 2 in directory NUMBERS_2
11 12 13 14 15 16 17 18 19 20
The incrementer is at 3 in directory NUMBERS_3
21 22 23 24 25 26 27 28 29 30
The incrementer is at 4 in directory NUMBERS_4
31 32 33 34 35 36 37 38 39 40
The incrementer is at 5 in directory NUMBERS_5
41 42 43 44 45 46 47 48 49 50
The incrementer is at 6 in directory NUMBERS_6
51 52 53 54 55 56 57 58 59 60
The incrementer is at 7 in directory NUMBERS_7
61 62 63 64 65 66 67 68 69 70
The incrementer is at 8 in directory NUMBERS_8
71 72 73 74 75 76 77 78 79 80
The incrementer is at 9 in directory NUMBERS_9
81 82 83 84 85 86 87 88 89 90
The incrementer is at 10 in directory NUMBERS_10
91 92 93 94 95 96 97 98 99 100
The standard output being sent to the screen is totally logical, but the text files are not in their appropriate directories, and somehow the files are empty.
What's going on?
Thanks!

Answer 1

my $file = "FILE_$i.txt";
should be
my $file = "$_/FILE_$i.txt";
And get rid of that opendir; you never use the handle.