unit ungiamod ; { model for gravitational field of our giants }
interface
var { global variables }
  MaxZonHarm    : byte ; { for maximum number of zonal harmonics }
  PlanetFM      : extended ; { planetograv const in km^3/s^2 }
  PlanetFMain   : extended ; { planetograv const in AU^3/day^2 }
  PlanetRadius  : extended ; { equatorial radius in AU for the forces }
  ZonHarmValue  : array[1..6] of extended ; { coefficient zonal harmonics }
{ gravitational model for each giant planet }
procedure toobtainmodel ( PlanetMain  : integer ) ;
implementation
uses
  unsagcot , { types const }
  ungiarom , { proc ToClcMatrOfRotation }
  unephjpl ; { const global variables and procedures }
{ gravitational model for each giant planet }
procedure toobtainmodel ( PlanetMain  : integer ) ;
var
  i  : byte ; { simple count }
begin
  MaxZonHarm:=0; { default nullo values }
  for i:=1 To 6 Do  ZonHarmValue[i]:=0.0; { default nullo values }
  ToObtainFMuS ; { from unephjpl for FactorMuS[..] global array }
  PlanetFM:=SunFM/SystemOfMasses[PlanetMain]; { km^3/s^2 unephjpl }
  PlanetFMain:=FactorMuS[PlanetMain]; { in AU^3/day^2 unephjpl }
  { EquatorMatRot is a matrix to change
    from the fixed equator of the Earth
      to the fixed equator of the Planet const unsagcot }
  ToClcMatrOfRotation(PlanetMain,jd2000,EquatorMatRot); { ungiarom global }
case  PlanetMain  of
  NJupiter :  { const unephjpl }
    begin
      PlanetRadius:=71492.0/AstrUnit; { in AU }
      MaxZonHarm:=6;
      ZonHarmValue[2]:=+0.014736;
      ZonHarmValue[3]:=+0.000001;
      ZonHarmValue[4]:=-0.000587;
      ZonHarmValue[6]:=+0.000103;
    end;
  NSaturn  :
    begin
      PlanetRadius:=60268.0/AstrUnit; { in AU }
      MaxZonHarm:=6;
      ZonHarmValue[2]:=+0.016292;
      ZonHarmValue[4]:=-0.000931;
      ZonHarmValue[6]:=+0.000091;
    end;
  NUranus  :
    begin
      PlanetRadius:=25559.0/AstrUnit; { in AU }
      MaxZonHarm:=4;
      ZonHarmValue[2]:=+0.00334346;
      ZonHarmValue[4]:=-0.00002885;
    end;
  NNeptune :
    begin
      PlanetRadius:=24764.0/AstrUnit; { in AU }
      MaxZonHarm:=4;
      ZonHarmValue[2]:=+0.003410;
      ZonHarmValue[4]:=-0.000035;
    end;
end; { for case of planet main }
end;
end.