I have a tab-delimited text file of an unspecified number (say x) columns. I want to split this into x-1 separate tab-delimited text files where the first file contains just the first and second columns, the second file contains the first and third columns, etc.

As I don't know the number of columns in advance, the filehandles for the output files have to be variables. So I have the following code:


use strict;

my $number_of_files = 0;

while (<STDIN>) {
    chomp;
    
    my @line = split;
    
    # On the first list, set up the process
    
    if ($. == 1) {
        for (my $i = 1; $i < @line; $i++) {
        
            my $fh = "OUTPUT" . $i;
            my $filename = $line[$i] . ".txt";
                
            open ($fh, ">$filename") or die "Cannot open the output fi
+le: $!";
                        
        }
        
        $number_of_files = @line;
        
    }
    
    else {
        for (my $i = 1; $i < @line; $i++) {
        
            my $fh = "OUTPUT" . $i;
            print $fh ("$line[0]\t$line[$i]\n");
            
        }
        
    }
    
}

for (my $i = 1; $i <= $number_of_files; $i++) {
    my $fh = "OUTPUT" . $i;
    close $fh or die "Cannot close the output file: $!";
            
}

[download]

The problem is I get a "Can't use string ("OUTPUT1") as a symbol ref while "strict refs" in use" error. Where have I gone wrong?

In reply to Multiple simultaneous filehandles by ezekiel

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