The 46 model gets the Best feautures of the HP: 45, Plus a Printer. This desktop counterpart starts with the features users like best in the HP: 45... 48 high-level functions and operation, plus addition, substraction, multiplication and division. Mean and standard deviations. Conversions of length, weight and volume measurements to U.S. or metric standards. Conversion of vectors to either polar or rectangular coordinates. And up to 10-digit accuracy. But with the HP: 46 users also get a printout of every step of every operation for fast and easy re-checking. The alphanumeric impact printer lets users list the contents of the operational stack and registers, gives them error indications, and prints symbols, numbers and letters in red or black, or both, on standard paper tape.