use Data::Table; $joinTable->colsMap( sub { $_->[4] = to_int_or_zero( $_->[4] ) } ); sub to_int_or_zero { my $value = shift; if ( defined($value) && ( $value =~ m/^\d+$/ || $value =~ m/^-?\d+\.?d*$/ ) ) { return $value; } else { return 0; } }