Hi, Monks. I'm very new to Perl and programing. But I'm stuck right now. First, the code:

#!/usr/bin/perl
use warnings;
no warnings 'uninitialized';
#Calculating Protein Mass

($input) = $ARGV[0];
open ($in, "<", $input) || die "Can't open \"$input\".\nError = $!.\n"
+;

$protein = <$in>;
my(%mass_values) = (
  'A' => 71.03711, 'C' => 103.00919, 'D' => 115.02694,
  'E' => 129.04259, 'F' => 147.06841, 'G' => 57.02146,
  'H' => 137.05891, 'I' => 113.08406, 'K' => 128.09496,
  'L' => 113.08406, 'M' => 131.04049, 'N' => 114.04293,
  'P' => 97.05276, 'Q' => 128.05858, 'R' => 156.10111,
  'S' => 87.03203, 'T' => 101.04768, 'V' => 99.06841,
  'W' => 186.07931, 'Y' => 163.06333, 
);

my $mass = "";

for(my $i=0;$i<length($protein);$i+=1) {
  $codon = substr($protein,$i,1);
  $mass .= "$mass_values{$codon}\n";
}

print $mass;

($result) = $ARGV[1];
open ($out, ">", $result) || die "Can't write to \"$result\".\nError =
+ $!.\n";
print $out "$mass";
close "$out";

exit;
[download]

This program is for this problem: http://rosalind.info/problems/prtm/

In order to run it, you need a protein string file, but you need to be registered to get one from rosalind, but here is the data string I'm using: https://justpaste.it/1cfuo

Now, this program I've written is just a modification of some codes I found here and there (And I kinda understand how it works). There is probably better ways of doing it, so just say if you see a quicker and easier solution!

Anyway, I'm stuck at the part were I have to sum up all the numbers. Right now, if I run it, I will just get a long list of numbers like this:

103.00919

131.04049

113.08406

57.02146

186.07931

128.09496

156.10111

97.05276

etc.

But I've no idea how to sum it all up. I've tried to make it into an array, but then I get errors saying "this is not a number", because I think perl thinks all of the different numbers is one element, and not 1000 different elements...

Anyway, I did complete the problem by "writing"(stole and modified) a separate program to sums it all up:

#!/usr/bin/perl
use strict;
use warnings;
 
# given a file with a number on each row, print the sum of the numbers
 
my $sum = 0;
my $filename = "result.txt";
open(my $fh, "<", $filename) or die "Could not open '$filename'\n";
while (my $line = <$fh>) {
    $sum += $line;
}
print "The total value is $sum\n";
[download]

(I did try to put the above code into the first program, so that the program writes to the results file, then opens the results file, and then does the addition. But for some reason, I get the wrong answer doing it this way, like it skips adding some numbers for some reason...

But I feel that this is something that can be done easily with just one perl program. But it was just my way of bodging it.

Anyway, hope someone can correct me and explain my mistakes!