拆分一列然后求和并将求和推入perl中的数组

Question

I have a file that looks like this:

LOCUS POS ALIAS VAR TEST P I DESC  
CCL23|disruptive chr17:34340329..34340854        .       2       BURDEN  1       0.43    0/1  
CCL23|disruptive     chr17:34340329..34340854        .       2       BURDEN  1       0.295   0/1  
CCL23|disruptive      chr17:34340329..34340854        .       2       BURDEN  1       0.005   1/1  
CCL23|disruptive     chr17:34340329..34340854        .       2       BURDEN  0.676617        0.005   1/0  

I want to split the last field by "/", then sum those numbers, and push another column on with the sum. For example, I would want the output to look like:

CCL23|disruptive chr17:34340329..34340854        .       2       BURDEN  1       0.43    0/1 1  
CCL23|disruptive     chr17:34340329..34340854        .       2       BURDEN  1       0.295   0/1 1  
CCL23|disruptive      chr17:34340329..34340854        .       2       BURDEN  1       0.005   1/1 2  
CCL23|disruptive     chr17:34340329..34340854        .       2       BURDEN  0.676617        0.005   1/0 1  

I have this code, but it doesn't work:

#! perl -w

my $file1 = shift@ARGV;

my $NVAR=0;
my @vars;
open (IN, $file1) or die "couldn't read file one";
while(<IN>){
    my@L=split;
    next if ($L[0] =~ m/LOCUS/);
    my@counts=split /\//, $L[7];
    foreach (@counts){
        $NVAR=${$_}[0] + ${$_}[1];
    }

    push @vars,[$L[0],$L[1],$L[2],$L[3],$L[4],$L[5],$L[6],$L[7],$NVAR];
}

close IN;

print "LOCUS POS ALIAS NVAR TEST P I DESC SUM\n";
foreach(@vars){
    print "@{$_}\n";
}

Any help is appreciated.

Answer 1

Always include use strict; and use warnings; at the top of EVERY script.

Limit your variables to the smallest scope possible, as declaring $NVAR outside of the while loop introduced a bug. Your summation can be fixed by the following:

my $NVAR = 0;
foreach (@counts){
    #$NVAR=${$_}[0] + ${$_}[1];  <-- this was bad.
    $NVAR += $_;
}

However, this can be solved using a perl oneliner

perl -MList::Util=sum -lane 'push @F, sum split "/", $F[-1]; print "@F"' file.txt 

Or if you have a header row:

perl -MList::Util=sum -lane '
        push @F, $. == 1 ? "SUM" : sum split "/", $F[-1];
        print "@F"
    ' file.txt 

Note, you can also utilize List::Util sum in your script as well.