in reply to Re^3: Find the boundaries of a substring in a string
in thread Find the boundaries of a substring in a string

Counting from 0, as usual. If you check the first substring, then it starts (correctly) at 9, but it should end at 20, not 21, am I wrong? It has a length of 12, and it includes position 9.
  • Comment on Re^4: Find the boundaries of a substring in a string

Replies are listed 'Best First'.
Re^5: Find the boundaries of a substring in a string
by hippo (Archbishop) on Jun 27, 2023 at 09:36 UTC

    In that case, subtract 1 from the end value and you are good to go:

    use strict;
use warnings;

my $seq =
  'dddddddddBBBBBBBBBBBBDDDDDDDDBBBBBBBBBBBBBBddddddddddddddddddddBBBB
+BBBBBBBBBBDDBBBBBBBBddddddddddddd';

while ($seq =~ /(B+)/g) {
    my $seg        = $1;
    my $seg_length = length ($seg);
    my $seg_end    = pos ($seq) - 1;
    my $seg_start  = $seg_end - $seg_length + 1;

    print $seg. "|" . $seg_start . "-" . $seg_end . "\n";
}

    [download]
    $ perl 11153140.pl 
BBBBBBBBBBBB|9-20
BBBBBBBBBBBBBB|29-42
BBBBBBBBBBBBBB|63-76
BBBBBBBB|79-86
$

    [download]

    🦛

[reply]
[d/l]
[select]
Re^5: Find the boundaries of a substring in a string
by Anonymous Monk on Jun 27, 2023 at 09:35 UTC
    I added that and it works fine now, thank you!
    
my $seg_end    = pos ($seq)-1;
    my $seg_start  = $seg_end - $seg_length+1;

    [download]
[reply]
[d/l]

In Section Seekers of Perl Wisdom