The Museum of HP Calculators

HP Forum Archive 19

 hp50g stackMessage #1 Posted by Sok-khieng Chum Hun on 17 Sept 2010, 7:10 a.m. Hello everyone, Do any of you know an application that displays the calculation while in rpn mode on the 50g like it does when in algebraic mode? Thank you :)

 Re: hp50g stackMessage #2 Posted by Crawl on 17 Sept 2010, 2:24 p.m.,in response to message #1 by Sok-khieng Chum Hun Um, it depends on exactly what you want to do? In my opinion, this is not the sort of thing that needs an "application". It is too simple a problem. Often the easiest thing to do if you want a record of your calculation AND a numerical result is to just hit ENTER, then ->NUM. Then the unevaluated expression is in level 2 and the number is in level 1. Say you're working completely with numbers, though. Then everything will be evaluated as you enter it, right? Here's a trick around it: Enter the first step as an algebraic object. Let's say you want to enter sin(1+2*(3-4)^(1/2)). Hit ' 3-4 Enter. You should have '3.-4.' on the stack. Alternatively, enter 3-4 with the equation writer. Then you can use RPN normally. The rest of the steps: 2 1/x ^ 2* 1 + sin you will then have sin((3.-4.)^(0.5)*2.+1.) on the stack. Hit Enter and then EVAL. The equation will be in level 2, the result in level 1. A couple of caveats: You must be in approx. mode. (Also, for this particular example, complex mode) Also, sometimes square roots, for whatever reason, trigger an EVAL. That's why we raised to the 0.5 power instead.

 Re: hp50g stackMessage #3 Posted by Sok-khieng Chum Hun on 17 Sept 2010, 5:54 p.m.,in response to message #2 by Crawl Wow! That trick is cool! Now I can even work on my 48gx and my university team mates won't doubt about my calculations! Thank you alot :)

 Re: hp50g stackMessage #4 Posted by Martin Pinckney on 17 Sept 2010, 8:33 p.m.,in response to message #3 by Sok-khieng Chum Hun Indeed, that is cool, Crawl. Even works on my 48sx dinosaur! Once the whole equation is on the stack, just press [VIEW] to see it in Equation Writer (similar to Textbook), then hit [ATTN] to return to where you were.

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