rk4.h

#include <array>
 
#include "Atmosphere.h"
 
#pragma once
 
using std::array;
 
class rk4 {
   public:
    rk4();
 
    array<float, 2> accel(array<float, 2> u, float rho);
 
    array<float, 2> rk4_step(array<float, 2> state, float dt, float rho);
 
    array<float, 2> sim_apogee(array<float, 2> state, float dt);
 
    float cd(float alt, float vel);
    array<double, 151> poly = {
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   private:
    Atmosphere atmo_;
    array<float, 2> y1{{0, 0}};
    array<float, 2> y2{{0, 0}};
    array<float, 2> y3{{0, 0}};
    array<float, 2> y4{{0, 0}};
    array<float, 2> rk4_kp1{{0, 0}};
};