How can I use Perl to concatenate array elements between two indexes?

Question

I have an array of strings: @array

I want to concatenate all strings beginning with array index $i to $j. How can I do this?

Answer 1

$newstring = join('', @array[$i..$j])

Answer 2

my $foo = join '', @array[$i..$j];

First we generate an array slice with the values that we want, then we join them on the empty character ''.

Answer 3

Try this ....

use warnings ;
use strict ;
use Data::Dumper ;
my $string ;
map { $string .=  $_; } @arr[$i..$j] ;
print $string ;

Answer 4

Just enclosing a perl array in quotes is enough to concatenate it, if you're happy with spaces as the concatenation character:

@array = qw(a b c d e f g);
$concatenated = "@array[2 .. 5]";
print $concatenated;
## prints "c d e f"

or of course

$" = '-';
@array = qw(a b c d e f g);
$concatenated = "@array[2 .. 5]";
print $concatenated;

if you'd prefer "c-d-e-f".

Answer 5

When trying to concatenate strings within an array as explained above, I get the following error message:

Argument "" isn't numeric in array element at ./orf.pl line 135, <GEN0> line 1.

I used:

my $newstring = join ('', $digested[$c][$i .. $i+$c+1]);

where $c runs from 0 to 3 and $i from 0 to 2. All elements in the array @digested contain strings. $newstring contains only the first element of the ones that should be joined.

Any hints?