C++ method from Objective C

Question

I want to call C++ TruePhase method from Objective C and I have no idea how to do it. Can anybody help me? Part of C++ file

#ifndef AAPLUS_EXT_CLASS
#define AAPLUS_EXT_CLASS
#endif    

class AAPLUS_EXT_CLASS CAAMoonPhases
    {
    public:
      static double K(double Year);
      static double MeanPhase(double k);
      static double TruePhase(double k);
    };

EDIT

There's no object in source or I don't know how the object looks like in C++. How to deal with it? Source:

#include "stdafx.h"
#include "AAMoonPhases.h"
#include "AACoordinateTransformation.h"
#include <cmath>
#include <cassert>
using namespace std;


//////////////////////////// Implementation ///////////////////////////////////

double CAAMoonPhases::K(double Year)
{
  return 12.3685*(Year - 2000);
}

double CAAMoonPhases::MeanPhase(double k)
{
  //convert from K to T
  double T = k/1236.85;
  double T2 = T*T;
  double T3 = T2*T;
  double T4 = T3*T;

  return 2451550.09766 + 29.530588861*k + 0.00015437*T2 - 0.000000150*T3 + 0.00000000073*T4;
}

double CAAMoonPhases::TruePhase(double k)
{
  //What will be the return value
  double JD = MeanPhase(k);

  //convert from K to T
  double T = k/1236.85;
  double T2 = T*T;
  double T3 = T2*T;
  double T4 = T3*T;

  double E = 1 - 0.002516*T - 0.0000074*T2;
  double E2 = E*E;

  double M = CAACoordinateTransformation::MapTo0To360Range(2.5534 + 29.10535670*k - 0.0000014*T2 - 0.00000011*T3);
  M = CAACoordinateTransformation::DegreesToRadians(M);
  double Mdash = CAACoordinateTransformation::MapTo0To360Range(201.5643 + 385.81693528*k + 0.0107582*T2 + 0.00001238*T3 - 0.000000058*T4); 
  Mdash = CAACoordinateTransformation::DegreesToRadians(Mdash);
  double F = CAACoordinateTransformation::MapTo0To360Range(160.7108 + 390.67050284*k - 0.0016118*T2 - 0.00000227*T3 + 0.000000011*T4);
  F = CAACoordinateTransformation::DegreesToRadians(F);
  double omega = CAACoordinateTransformation::MapTo0To360Range(124.7746 - 1.56375588*k + 0.0020672*T2 + 0.00000215*T3);
  omega = CAACoordinateTransformation::DegreesToRadians(omega);
  double A1 = CAACoordinateTransformation::MapTo0To360Range(299.77 + 0.107408*k - 0.009173*T2);
  A1 = CAACoordinateTransformation::DegreesToRadians(A1);
  double A2 = CAACoordinateTransformation::MapTo0To360Range(251.88 + 0.016321*k);
  A2 = CAACoordinateTransformation::DegreesToRadians(A2);
  double A3 = CAACoordinateTransformation::MapTo0To360Range(251.83 + 26.651886*k);
  A3 = CAACoordinateTransformation::DegreesToRadians(A3);
  double A4 = CAACoordinateTransformation::MapTo0To360Range(349.42 + 36.412478*k);
  A4 = CAACoordinateTransformation::DegreesToRadians(A4);
  double A5 = CAACoordinateTransformation::MapTo0To360Range(84.66 + 18.206239*k);
  A5 = CAACoordinateTransformation::DegreesToRadians(A5);
  double A6 = CAACoordinateTransformation::MapTo0To360Range(141.74 + 53.303771*k);
  A6 = CAACoordinateTransformation::DegreesToRadians(A6);
  double A7 = CAACoordinateTransformation::MapTo0To360Range(207.14 + 2.453732*k);
  A7 = CAACoordinateTransformation::DegreesToRadians(A7);
  double A8 = CAACoordinateTransformation::MapTo0To360Range(154.84 + 7.306860*k);
  A8 = CAACoordinateTransformation::DegreesToRadians(A8);
  double A9 = CAACoordinateTransformation::MapTo0To360Range(34.52 + 27.261239*k);
  A9 = CAACoordinateTransformation::DegreesToRadians(A9);
  double A10 = CAACoordinateTransformation::MapTo0To360Range(207.19 + 0.121824*k);
  A10 = CAACoordinateTransformation::DegreesToRadians(A10);
  double A11 = CAACoordinateTransformation::MapTo0To360Range(291.34 + 1.844379*k);
  A11 = CAACoordinateTransformation::DegreesToRadians(A11);
  double A12 = CAACoordinateTransformation::MapTo0To360Range(161.72 + 24.198154*k);
  A12 = CAACoordinateTransformation::DegreesToRadians(A12);
  double A13 = CAACoordinateTransformation::MapTo0To360Range(239.56 + 25.513099*k);
  A13 = CAACoordinateTransformation::DegreesToRadians(A13);
  double A14 = CAACoordinateTransformation::MapTo0To360Range(331.55 + 3.592518*k);
  A14 = CAACoordinateTransformation::DegreesToRadians(A14);

  //convert to radians
  double kint = 0;
  double kfrac = modf(k, &kint);
  if (kfrac < 0)
    kfrac = 1 + kfrac;
  if (kfrac == 0) //New Moon
  {
    double DeltaJD = -0.40720*sin(Mdash) +
          0.17241*E*sin(M) +
          0.01608*sin(2*Mdash) +
          0.01039*sin(2*F) +
          0.00739*E*sin(Mdash - M) +
          -0.00514*E*sin(Mdash + M) +
          0.00208*E2*sin(2*M) +
          -0.00111*sin(Mdash - 2*F) +
          -0.00057*sin(Mdash + 2*F) +
          0.00056*E*sin(2*Mdash + M) +
          -0.00042*sin(3*Mdash) +
          0.00042*E*sin(M + 2*F) +
          0.00038*E*sin(M - 2*F) +
          -0.00024*E*sin(2*Mdash - M) +
          -0.00017*sin(omega) +
          -0.00007*sin(Mdash + 2*M) +
          0.00004*sin(2*Mdash - 2*F) +
          0.00004*sin(3*M) +
          0.00003*sin(Mdash + M - 2*F) +
          0.00003*sin(2*Mdash + 2*F) +
          -0.00003*sin(Mdash + M + 2*F) +
          0.00003*sin(Mdash - M + 2*F) +
          -0.00002*sin(Mdash - M - 2*F) +
          -0.00002*sin(3*Mdash + M) +
          0.00002*sin(4*Mdash);
    JD += DeltaJD;
  }
  else if ((kfrac == 0.25) || (kfrac == 0.75)) //First Quarter or Last Quarter
  {
    double DeltaJD = -0.62801*sin(Mdash) +
          0.17172*E*sin(M) +
          -0.01183*E*sin(Mdash + M) +
          0.00862*sin(2*Mdash) +
          0.00804*sin(2*F) +
          0.00454*E*sin(Mdash - M) +
          0.00204*E2*sin(2*M) +
          -0.00180*sin(Mdash - 2*F) +
          -0.00070*sin(Mdash + 2*F) +
          -0.00040*sin(3*Mdash) +
          -0.00034*E*sin(2*Mdash - M) +
          0.00032*E*sin(M + 2*F) +
          0.00032*E*sin(M - 2*F) +
          -0.00028*E2*sin(Mdash + 2*M) +
          0.00027*E*sin(2*Mdash + M) +
          -0.00017*sin(omega) +
          -0.00005*sin(Mdash - M - 2*F) +
          0.00004*sin(2*Mdash + 2*F) +
          -0.00004*sin(Mdash + M + 2*F) +
          0.00004*sin(Mdash - 2*M) +
          0.00003*sin(Mdash + M - 2*F) +
          0.00003*sin(3*M) +
          0.00002*sin(2*Mdash - 2*F) +
          0.00002*sin(Mdash - M + 2*F) +
          -0.00002*sin(3*Mdash + M);
    JD += DeltaJD;

    double W = 0.00306 - 0.00038*E*cos(M) + 0.00026*cos(Mdash) - 0.00002*cos(Mdash - M) + 0.00002*cos(Mdash + M) + 0.00002*cos(2*F);
    if (kfrac == 0.25) //First quarter
      JD += W;
    else
      JD -= W;          
  }
  else if (kfrac == 0.5) //Full Moon
  {
    double DeltaJD = -0.40614*sin(Mdash) +
          0.17302*E*sin(M) +
          0.01614*sin(2*Mdash) +
          0.01043*sin(2*F) +
          0.00734*E*sin(Mdash - M) +
          -0.00514*E*sin(Mdash + M) +
          0.00209*E2*sin(2*M) +
          -0.00111*sin(Mdash - 2*F) +
          -0.00057*sin(Mdash + 2*F) +
          0.00056*E*sin(2*Mdash + M) +
          -0.00042*sin(3*Mdash) +
          0.00042*E*sin(M + 2*F) +
          0.00038*E*sin(M - 2*F) +
          -0.00024*E*sin(2*Mdash - M) +
          -0.00017*sin(omega) +
          -0.00007*sin(Mdash + 2*M) +
          0.00004*sin(2*Mdash - 2*F) +
          0.00004*sin(3*M) +
          0.00003*sin(Mdash + M - 2*F) +
          0.00003*sin(2*Mdash + 2*F) +
          -0.00003*sin(Mdash + M + 2*F) +
          0.00003*sin(Mdash - M + 2*F) +
          -0.00002*sin(Mdash - M - 2*F) +
          -0.00002*sin(3*Mdash + M) +
          0.00002*sin(4*Mdash);
    JD += DeltaJD;
  }
  else
  {
    assert(false);
  }

  //Additional corrections for all phases
  double DeltaJD2 = 0.000325*sin(A1) +
        0.000165*sin(A2) +
        0.000164*sin(A3) +
        0.000126*sin(A4) +
        0.000110*sin(A5) +
        0.000062*sin(A6) +
        0.000060*sin(A7) +
        0.000056*sin(A8) +
        0.000047*sin(A9) +
        0.000042*sin(A10) +
        0.000040*sin(A11) +
        0.000037*sin(A12) +
        0.000035*sin(A13) +
        0.000023*sin(A14);
  JD += DeltaJD2;

  return JD;
}

possible duplicate of [Mixing Objective-C and C++](http://stackoverflow.com/questions/2710507/mixing-objective-c-and-c) — molbdnilo, Jun 30 '15 at 11:37

Homam · Answer 1 · 2015-07-01T03:50:33.853

1

You can do that by using Objective C++.
Here are the steps:
1) Change the extension of your Objective-C implementation file from .m to .mm to convert it to Objective C++.
2) Now Import the header file into your Objective C++
3) Now create the object and call the method.
For eg.

CppClass * cppObject = new CppClass()
cppObject->aMethod()

Please do remember to delete the object explicitly when you are done with it, to destroy it, if you create the object using above method.

delete cppObject;

Or else you could simply use the below method, where you don't need to explicitly delete the object. It will get destroyed automatically when it will get out of scope in which it was declared.

CppClass cppObject;
cppObject.aMethod()

edited Jul 01 '15 at 03:50

answered Jun 30 '15 at 11:42

Homam

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Why unnecessary heap allocation? – celticminstrel Jun 30 '15 at 11:56
@celticminstrel, thanks for pointing out. Added more detail to the answer. – Homam Jul 01 '15 at 03:53
Question is in the answer because its too long and contains code. – pettyBright Jul 01 '15 at 08:54
@pettyBright, do not add question in the answer. And even the question you posted in answer is different one from the one you asked. Ask different questions separately. – Homam Jul 02 '15 at 04:07

C++ method from Objective C

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