okay thanks a lot. I'm almost there but found out that actually the columns I'm working on have a lot of numbers that have as a decimal separator a 'comma'. For example in the blank spot number like 2,3 as opposed to the 'space'. To work around that I thought to do 
sub to_int_or_zero {
  my $value = shift;
$value =~ s/,/\./;
  if (defined($value) &&
      $value =~ m/^\d+$/) {
    return $value;
  } else {
    return 0;
  }
}

[download]
but it doesn't work. The 2,3 nicely changes into 2.3 but I'm obviously making a very elementary mistake that I can't understand myself at this moment as the row adds up to ... 3
: (

In reply to Re^3: Data::Table - empty values - avoid warnings by GertMT
in thread Data::Table - empty values - avoid warnings by GertMT

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