[BASIC HELP] CAS.fsolve problem [Solved]

[Ziz]

Thank you! This clarifies the things.

(03-22-2019 04:35 PM)DrD Wrote:  I see that Road has a workable program, and I was just about to post the same thing. The big issues are:

1. EXPORT the program.
2. T and P are RESERVED variables, so don't make a local variable P.
3. Use a string inside the CAS command.

Here is what I ended up with: Pws(5) ==> 3.45704603787ᴇ119

Code:


EXPORT Pws(T)
BEGIN

  LOCAL C1,C2,C3,C4,C5,C6,C7;
  LOCAL Ps;  //  Omitted Var P, as it is a reserved variable

  T:=T+273.15;  // T is reserved variable also

  C1:=-5.6745359*10^3;
  C2 := 6.3925247*10;
  C3 := −9.6778430/10^(3);
  C4 := 6.2215701/10^(7);
  C5 := 2.0747825/10^(9);
  C6 := −9.4840240/10^(13);
  C7 := 4.1635019*10;

  Ps:=CAS.fsolve("C1/T+C2+C3*T+C4*T^2+C5*T^3+C6*T^4+C7*ln(T)=ln(P),P,1000"); // Note:  Usage of double quotes in CAS command

// PRINT("Ps="+Ps);

  RETURN Ps;
END;