How to use RPN mode with Functions? - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: HP Calculators (and very old HP Computers) (/forum-3.html) +--- Forum: HP Prime (/forum-5.html) +--- Thread: How to use RPN mode with Functions? (/thread-7853.html) How to use RPN mode with Functions? - lemontea - 03-03-2017 12:05 AM Hello - I bought a Prime ages ago but only recently tried to use it. My 15C had been quite sufficient thus far. Anyway I entered a function definition and then tried to resolve it at the Home screen using Textbook entry, and it was fine. But when I switch to RPN mode I get a syntax error. E.g., if I define F1 = X^2 (for example) Textbook mode, I press Vars and then find the symbolic F1 entry, it shows F1 on the Home screen. Then I press the () key and then enter, say, 5. Then ENTER, and it would resolve to F(5) which is 25. But RPN mode doesn't work. Gets error. RE: How to use RPN mode with Functions? - Han - 03-03-2017 12:16 AM In RPN entry, you need to place the argument(s) onto the stack. Then you would execute a command using COMMAND(n) where n is the number of arguments used by COMMAND. In this case, your command is F1. In algebraic notation, you would enter F1(5) to get 25. In RPN notation, you would place 5 onto the stack, and type F1(1). RE: How to use RPN mode with Functions? - lemontea - 03-03-2017 12:37 AM (03-03-2017 12:16 AM)Han Wrote:  In RPN entry, you need to place the argument(s) onto the stack. Then you would execute a command using COMMAND(n) where n is the number of arguments used by COMMAND. In this case, your command is F1. In algebraic notation, you would enter F1(5) to get 25. In RPN notation, you would place 5 onto the stack, and type F1(1). Ok thanks. So if I define a function with X and Y, then I would enter Y and then X onto the stack, and then type F1(2) to tell it to use the last 2 entered parameters on the stack? RE: How to use RPN mode with Functions? - Han - 03-03-2017 12:52 AM (03-03-2017 12:37 AM)lemontea Wrote:   (03-03-2017 12:16 AM)Han Wrote:  In RPN entry, you need to place the argument(s) onto the stack. Then you would execute a command using COMMAND(n) where n is the number of arguments used by COMMAND. In this case, your command is F1. In algebraic notation, you would enter F1(5) to get 25. In RPN notation, you would place 5 onto the stack, and type F1(1). Ok thanks. So if I define a function with X and Y, then I would enter Y and then X onto the stack, and then type F1(2) to tell it to use the last 2 entered parameters on the stack? Yes, for a general 2-variable function. Usually, F1 is intended for a single-variable function. RE: How to use RPN mode with Functions? - lemontea - 03-03-2017 01:08 AM (03-03-2017 12:52 AM)Han Wrote:   (03-03-2017 12:37 AM)lemontea Wrote:  Ok thanks. So if I define a function with X and Y, then I would enter Y and then X onto the stack, and then type F1(2) to tell it to use the last 2 entered parameters on the stack? Yes, for a general 2-variable function. Usually, F1 is intended for a single-variable function. Thanks. But I am thinking maybe I should just use Textbook mode... sad to see RPN go.... RE: How to use RPN mode with Functions? - Tim Wessman - 03-03-2017 02:20 AM Note that specifying argument count only needs to be done when you have a variable number of arguments. RE: How to use RPN mode with Functions? - lemontea - 03-03-2017 02:53 AM (03-03-2017 02:20 AM)Tim Wessman Wrote:  Note that specifying argument count only needs to be done when you have a variable number of arguments. I tried not specifying anything and it didn't work. RE: How to use RPN mode with Functions? - Tim Wessman - 03-03-2017 03:05 AM (03-03-2017 02:53 AM)lemontea Wrote:  I tried not specifying anything and it didn't work. F1 can take a variable number of arguments. Use the define key, define a named function, and it wouldn't require it. Nor would something like CEIL, SIN, or similar.