[gecode-users] Help figuring out how to use float variables

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I have a simple model which I am trying to use to find one, two or possible
three floating variables that satisfies certain solutions to a formula. The
problem I face is that Gecode keeps giving thousands of the SAME solution,
probably because of truncation errors.
I've looked in the MPG, but can't find any information regarding how to do
this, so if anyone has any suggestions or hints, I'd be grateful.
I'm using Gist to find and print the solutions.
I'm attaching the code.

// FindConfidenceFormula.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"

class XFindConfidenceFormula: public Gecode::Space
{
private:
	static const int NumLevels = 2;
	Gecode::FloatVarArray R, r;
	Gecode::BoolVarArray RightSubtree;

public:
	XFindConfidenceFormula(): R(*this, NumLevels, 0, 1), r(*this, NumLevels, 0, 1), RightSubtree(*this, NumLevels, false, true)
	{
		static const double NodeConfValues[NumLevels] = { 0, 0.44 };

		for (int i = 0; i < NumLevels; i++)
		{
			Gecode::rel(*this, R[i], Gecode::FRT_EQ, Gecode::expr(*this, 1 - r[i]), RightSubtree[i]);
			Gecode::rel(*this, R[i], Gecode::FRT_EQ, r[i], Gecode::expr(*this, !RightSubtree[i]));
		}

		Gecode::LinFloatExpr Product = R[0];
		for (int i = 1; i < NumLevels; i++)
			Product = Product * R[i];

		for (int i = 1; i < NumLevels; i++)
			Gecode::rel(*this, Gecode::abs((R[i] - Product)/(1 - Product) - NodeConfValues[i]) < 1E-100);

		//for (int i = 1; i < NumLevels; i++)
		//	Gecode::rel(*this, Gecode::abs(r[i - 1] - r[i]) >= 0.01);

		Gecode::rel(*this, r[0] == 0);
		//Gecode::rel(*this, r[1] == 0.8);
		//Gecode::rel(*this, RightSubtree[0] == false);
		//Gecode::rel(*this, RightSubtree[1] == false);

		Gecode::branch(*this, RightSubtree, Gecode::INT_VAR_NONE(), Gecode::INT_VAL_MIN());
		Gecode::branch(*this, R, Gecode::FLOAT_VAR_NONE(), Gecode::FLOAT_VAL_SPLIT_MIN());
		Gecode::branch(*this, r, Gecode::FLOAT_VAR_NONE(), Gecode::FLOAT_VAL_SPLIT_MIN());
	}

	virtual Gecode::Space* copy(bool share)
	{
		return new XFindConfidenceFormula(share, *this);
	}

	XFindConfidenceFormula(bool share, XFindConfidenceFormula& that): Gecode::Space(share, that)
	{
		R.update(*this, share, that.R);
		r.update(*this, share, that.r);
		RightSubtree.update(*this, share, that.RightSubtree);
	}

	virtual void print(std::ostream& out) const
	{
		out << "Right subtree: " << RightSubtree << "\nR: " << R << "\n" << "r: " << r << "\n";
	}
};

int main()
{
	typedef XFindConfidenceFormula Model_t;
	Model_t Model;
	Gecode::Gist::Options options;
	Gecode::Gist::Print<Model_t> printer("Print solution");
	options.inspect.click(&printer);
	Gecode::Gist::dfs(&Model, options);
	return 0;
}
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