Solve Keplers equation - Printable Version

Solve Keplers equation - Printable Version

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Solve Keplers equation - Powersoft - 07-21-2022 02:43 PM

I wont to solve Keplers equation with this program,
but something is wrong with my guess.
Is it possible to solve this with one of the build in commands?

Code:

EXPORT Kepler()

BEGIN

  LOCAL M:=5;

  LOCAL e0:=0.1;

  LOCAL E;

  AAngle:=2;  // do calculations in degree

  // --------------------------------

  // wont to solve Kepler's equation:

  // E = M + e0 * SIN(E)

  // ---------------------------------

  E:=FNROOT(E-M-e0*SIN(E),E,1);

  PRINT(E);

END;

RE: Solve Keplers equation - Albert Chan - 07-21-2022 05:39 PM

Code:

  E:=FNROOT(E-M-e0*SIN(E),E,1);

I think FNROOT cannot lookup local variables. If (M,e0) are globals, above work.

Code:

  AAngle:=2;  // do calculations in degree

You may have to do "AAngle:=0;", to restore HOME default setting.

RE: Solve Keplers equation - matalog - 07-23-2022 11:32 AM

What equation do you actually want to solve? Give it in the form of var*bla1-bla2 (etc)=bla3, where var is the variable you want to solve for and bla1,2 and 3 are known numbers (even if they are stored as variables).

I'm sure we can write it in a form that the solve command will be able to work with.