comment on

Here are the comments to your program:

You don't use strict. You really should, as long as your program is more than several lines long. use warnings is also a bit better than perl -w because warnings pragma is local-scoped, but -w applies globally, including modules you use (but you are usually not supposed to fix warnings in them).
$b=print_sequence($a,3);
```
sub print_sequence {
my($sequence, $length) = @_;
for (my $pos = 0; $pos < length($sequence); $pos +=
$length ) {
print substr($sequence, $pos, $length), "\n";
}
}
[download]
```
You assign the $b variable the value of the expression print_sequence($a,3), but there is no return in your sub, so $b gets never assigned. You should return something from your sub if you want to assign it to a variable.
```
print"Cannot open file\"$output\".\n\n";
exit;
[download]
```
This can be done easier using die: die qq{Cannot open file "$output"\n\n};. You have some problems with your quoting. Perhaps reading Quote and Quote like Operators will help you.
You don't indent your program. Use Perl::Tidy, set up your editor to help you indenting the program or switch to another editor or IDE.

Sorry if my advice was wrong.

In reply to Re: Is it possible to write the results of a subroutine for data formatting to a text file? by aitap
in thread Is it possible to write the results of a subroutine for data formatting to a text file? by supriyoch_2008

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