HP Prime Graphing NW280AAABA manual Reverse Polish Notation RPN

However, you could also have entered the arguments separately and then, with a blank entry line, entered the operator (s). Your history would look like this before entering the operator:

If there are no entries in history and you enter an operator or function, an error message appears. An error message will also appear if there is an entry on a stack level that an operator needs but it is not an appropriate argument for that operator. For example, pressing fwhen there is a string on level 1 displays an error message.

An operator or function will work only on the minimum number of arguments necessary to produce a result. Thus if you enter on the entry line 2 4 6 8 and press s, stack level 1 shows 48.

Multiplication needs only two arguments, so the two arguments last entered are the ones that get multiplied. The entries 2 and 4 are not ignored: 2 is placed on stack level 3 and 4 on stack level 2.

Where a function can accept a variable number of arguments, you need to specify how many arguments you want it to include in its operation. You do this by specifying the number in parentheses straight after the function name. You then press Eto evaluate the function. For example, suppose your stack looks like this:

Suppose further that you want to determine the minimum of just the numbers on stack levels 1, 2, and 3. You choose the MIN function from the MATH menu and complete the entry as MIN(3). When you press E, the minimum of just the last three items on the stack is displayed.

50 Reverse Polish Notation (RPN)