I want to use perl to find fuzzy matches in a file of sequences and return the character number in the string at which the match is found with a given number of substitutions (lets say S=2). For example if my input file is:
Name1
ACTGTGACCTTT
Name2
ACCTTTACTGTG
Name3
GACCTTTCTGTG
Name4
GCACCTTTTGTG
Name5
GCTACCTTTGTG
Name6
ACTGACCTTTTG
Name7
ACTGTACCTTTG
Name8
ACCTTTACCTTT
Name9
ACTGTGACTGTG
and my search query is "ACCTTT".
Then I want my output to be something like:
Name1
6
Name2
0
Name3
1
Name4
2
Name5
3
Name6
4
Name7
5
Name8
0 6
I've tried doing this with String::Approx, but this module only returns the first index for each element of the array I am matching the query with. Also this module seems to be buggy and even when I set the number of Insertions and Deletions to 0, and allow for 2 substitutions, it still returns indexes for matches with many more than 2 substitutions.
Here is the code I was using (in case there is something I don't understand about this module).
#!/usr/bin/perl -w
use String::Approx 'aindex';
my $input_fasta=$ARGV[0];
open(IN,"<$input_fasta") || die ("Error opening $input_fasta $!");
my $l = 0;
my @names;
my @seqs;
while (<IN>){
if ($l % 2 == 0 ){
push (@names, $_);
}
elsif ($l % 2 ==1) {
push (@seqs, $_);
}
$l++;
}
my @hits = aindex("ACCTTT", ["I0", "D0", "S2"], @seqs);
$hl=0;
foreach (@hits){
if ($_ != -1){
print "$names[$hl]$_\n";
$hl++
}
else {
$hl++;
}
}
But this just returns:
Name1
6
Name2
0
Name3
1
Name4
1
Name5
1
Name6
0
Name7
5
Name8
0