Panasonic said Thursday it swung back to profit for the six months to September and doubled its full-year earnings forecast thanks to a weak yen and cost-cutting as it undergoes an overhaul. The electronics giant booked a 169.3 billion yen ($1.72 billion) net profit for the period, reversing a net loss of 685.2 billion yen a year earlier while it also  said it expects a 100 billion yen profit in the fiscal year to March.