HP 50G help

[Vtile]

(08-06-2016 12:11 PM)Hlib Wrote:  I had to ensure a proper understanding of my operation correctly with HP-50g, if I type 5 3 / EXE or <<5 3 />> EVAL, the calculator returns the result of 5/3, because the system flag -105 = 0 (exact mode) only works in manual mode. The program returns to me, for example, for << 105 SF 5 3 / >> or for <<105 CF 5 3 />> 1.6666 ... or sometimes 5/3 no matter if the user flag 105 = 1 or =0. The program returns 5/3 or 1.666 ... arbitrarily regardless of the system/user flags. I threw one of my HP-50g and bought another. But the problem persists. Rev 2.15.
Claudio, you have a special HP-50g calculator?

Did you mean

Code:

<< -105 SF 5 3 / >>

??? Exact mode can be used in programs also, I haven't found any hick-ups on that on UserRPL. Also regular 50g exact mode works differently if there is decimal number present. ie. there is difference how it works with calculations of

Code:

<< 5. 3 / >>

and

Code:

<< 5 3 / >>

while

Code:

<< 5. R->I 3 / >>

and

Code:

<< 5 3 / >>

should work the same. Also system flag -2 do enable partial "exact mode" for CAS, ie. if the calculation contains Pi symbol, it keeps the pi symbol and not give you aprox value, of the calculation until you use eval / ->num command.

R->I is command for converting real type numbers to integer type (get rid of that dot behind the number). XQ is another a bit different real / integer switch command.

Here is a small program to toggle between exact and approx mode. I did save it to one of the user keys for now.

Code:


<< -105 FS? -> X
  << IF 'X==1' THEN -105 CF "EXACT MODE" 1 DISP 1 FREEZE
       ELSE
       -105 SF "APPROX MODE" 1 DISP 1 FREEZE END
  >>
>>

And here is a small program to toggle between symbolic vs. numeric constants. ( System Flag 2 )

Code:


<< -2 FS? -> X 
<< IF 'X==1' THEN -2 CF "Pi = Pi Mode" 1 DISP 1 FREEZE ELSE
-2 SF "Pi = 3.142 Mode" 1 DISP 1 FREEZE 
END 
>> 
>>

And here is a program to toggle between the cylindrical and Rectangular modes. Now with proper RPN / RPL IF structure. (Original author unknown, maybe mr. Linares or maybe derived from HP28 era.)

Code:


<< -16 FS? -> X << X 0 == IF THEN CYLIN ELSE RECT END >> >>