BackwardEulerSolver.cpp
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	//
	// Created by Pablo on 12/2/18.
	//

	#include "BackwardEuler.hpp"
	#include <cmath>

	#define THRESH 50 //Max iter for fixed point method


	BackwardEulerSolver::BackwardEulerSolver() {}

	BackwardEulerSolver::~BackwardEulerSolver() {}

	void BackwardEulerSolver::SolveEquation(std::ostream &stream) {
	double y_prev = GetInitialValue();
	double y_next;

	double t_prev = GetInitialTime();
	double t_next;

	double h = GetStepSize();
	int n = static_cast<int>(std::floor((GetFinalTime() - GetInitialTime()) / h));

	stream << t_prev << " " << y_prev << "\n";

	for (int i = 1; i <= n; ++i) {
	y_next = y_prev;
	t_next = t_prev + h;
	// Fixed point iteration
	for (int j = 1; j <= THRESH; ++j) {
	y_next = y_prev + h * RightHandSide(y_next, t_next);
	}

	stream << t_next << " " << y_next << "\n";
	y_prev = y_next;
	t_prev = t_next;
	}
	}