Input data type for fsolve() for PPL - 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: Input data type for fsolve() for PPL (/thread-13203.html) Input data type for fsolve() for PPL - teerasak - 06-29-2019 12:27 PM I have a question when calling fsolve() in the program. When calling from cas screen, we can use fsolve() with the following: fsolve(, ) For example, fsolve(sin(x)/x = 0, x) When calling from program, what is the data type of , . I tried string, it doesn’t work. Any idea about this? RE: Input data type for fsolve() for PPL - DrD - 06-29-2019 03:26 PM When working with CAS commands in ppl, use the CAS command with quoted content, like this: Code: ``` EXPORT temp() BEGIN   LOCAL x,y;   CAS.fsolve("[x^2+y-2,x+y^2-2],[x,y],[0,0]"); END;``` RE: Input data type for fsolve() for PPL - teerasak - 06-29-2019 05:48 PM @DrD, thank you very much for your help. For the command you provided, it works. However, if I write the code like this: Code: ``` EXPORT temp() BEGIN   LOCAL x,y;   LOCAL equn;   equn := “[x^2+y-2,x+y^2-2],[x,y],[0,0]”;   RETURN CAS.fsolve(equn); END;``` It doesn’t work. It just return fsolve(equn). How can we have fsolve() or CAS.fsolve() accept the input from string variable? RE: Input data type for fsolve() for PPL - roadrunner - 06-30-2019 05:15 PM Try: EXPORT temp() BEGIN // LOCAL x,y; LOCAL equn; equn:="[x^2+y-2,x+y^2-2],[x,y],[0,0]"; RETURN CAS.fsolve(EVAL(equn)); END; -road RE: Input data type for fsolve() for PPL - teerasak - 07-01-2019 07:17 PM Thank you, roadrunner. That’s work! Why do we need to remove declaration of x, y variable? RE: Input data type for fsolve() for PPL - roadrunner - 07-02-2019 11:48 AM I was getting this error message when I used local variables: "fsolve([equations],[variables],[guesses]) Error: Bad Argument Value" I may be wrong, but I think when you call a CAS command from a program with local variables it used the value stored in the variable so it was really trying to do this: fsolve([0^2+0-2,0+0^2-2],[0,0],[0,0]) which generated that error message. It's best to use undefined variables for fsolve. -road RE: Input data type for fsolve() for PPL - teerasak - 07-02-2019 01:21 PM ok. got the point. thank you RE: Input data type for fsolve() for PPL - DrD - 07-02-2019 07:11 PM (07-01-2019 07:17 PM)teerasak Wrote:  Thank you, roadrunner. That’s work! Why do we need to remove declaration of x, y variable? You can make the variables local to the entire scope of the program: Code: ``` LOCAL x,y; EXPORT temp() BEGIN // LOCAL x,y;   LOCAL equn;   equn:="[x^2+y-2,x+y^2-2],[x,y],[0,0]";   RETURN CAS.fsolve(EVAL(equn)); END;```