Yes OK, try 
my @dates  = (defined $hash{$pk}[1]) ? @{$hash{$pk}[1]} : ();
my @rdates = (defined $hash{$pk}[2]) ? @{$hash{$pk}[2]} : ();

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poj

In reply to Re^5: combining 2 files with 4 columns need help by poj
in thread combining 2 files with 4 columns need help by rruser

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