fixing examples

example/Vector/4_reorder/energy_force.hpp

+/*
+ * energy_force.hpp
+ *
+ *  Created on: Aug 6, 2016
+ *      Author: i-bird
+ */
+
+#ifndef EXAMPLE_VECTOR_4_REORDER_ENERGY_FORCE_HPP_
+#define EXAMPLE_VECTOR_4_REORDER_ENERGY_FORCE_HPP_
+
+constexpr int velocity = 0;
+constexpr int force = 1;
+
+
+void calc_forces(vector_dist<3,double, aggregate<double[3],double[3]> > & vd, CellList<3, double, FAST, shift<3, double> > & NN, double sigma12, double sigma6)
+{
+	// update the Cell-list
+	vd.updateCellList(NN);
+
+	// Get an iterator over particles
+	auto it2 = vd.getDomainIterator();
+
+	// For each particle p ...
+	while (it2.isNext())
+	{
+		// ... get the particle p
+		auto p = it2.get();
+
+		// Get the position xp of the particle
+		Point<3,double> xp = vd.getPos(p);
+
+		// Reset the forice counter
+		vd.template getProp<force>(p)[0] = 0.0;
+		vd.template getProp<force>(p)[1] = 0.0;
+		vd.template getProp<force>(p)[2] = 0.0;
+
+		// Get an iterator over the neighborhood particles of p
+		auto Np = NN.template getNNIterator<NO_CHECK>(NN.getCell(vd.getPos(p)));
+
+		// For each neighborhood particle ...
+		while (Np.isNext())
+		{
+			// ... q
+			auto q = Np.get();
+
+			// if (p == q) skip this particle
+			if (q == p.getKey())	{++Np; continue;};
+
+			// Get the position of p
+			Point<3,double> xq = vd.getPos(q);
+
+			// Get the distance between p and q
+			Point<3,double> r = xp - xq;
+
+			// take the norm of this vector
+			double rn = norm2(r);
+
+			// Calculate the force, using pow is slower
+			Point<3,double> f = 24.0*(2.0 *sigma12 / (rn*rn*rn*rn*rn*rn*rn) -  sigma6 / (rn*rn*rn*rn)) * r;
+
+			// we sum the force produced by q on p
+			vd.template getProp<force>(p)[0] += f.get(0);
+			vd.template getProp<force>(p)[1] += f.get(1);
+			vd.template getProp<force>(p)[2] += f.get(2);
+
+			// Next neighborhood
+			++Np;
+		}
+
+		// Next particle
+		++it2;
+	}
+}
+
+
+double calc_energy(vector_dist<3,double, aggregate<double[3],double[3]> > & vd, CellList<3, double, FAST, shift<3, double> > & NN, double sigma12, double sigma6)
+{
+	double E = 0.0;
+
+	// Update the cell-list
+	vd.updateCellList(NN);
+
+	// Get the iterator
+	auto it2 = vd.getDomainIterator();
+
+	// For each particle ...
+	while (it2.isNext())
+	{
+		// ... p
+		auto p = it2.get();
+
+		// Get the position of the particle p
+		Point<3,double> xp = vd.getPos(p);
+
+		// Reset the force
+		vd.template getProp<force>(p)[0] = 0.0;
+		vd.template getProp<force>(p)[1] = 0.0;
+		vd.template getProp<force>(p)[2] = 0.0;
+
+		// Get an iterator over the neighborhood of the particle p
+		auto Np = NN.template getNNIterator<NO_CHECK>(NN.getCell(vd.getPos(p)));
+
+		// For each neighborhood of the particle p
+		while (Np.isNext())
+		{
+			// Neighborhood particle q
+			auto q = Np.get();
+
+			// if p == q skip this particle
+			if (q == p.getKey())	{++Np; continue;};
+
+			// Get position of the particle q
+			Point<3,double> xq = vd.getPos(q);
+
+			// take the normalized direction
+			double rn = norm2(xp - xq);
+
+			// potential energy (using pow is slower)
+			E += 4.0 * ( sigma12 / (rn*rn*rn*rn*rn*rn) - sigma6 / ( rn*rn*rn) );
+
+			// Next neighborhood
+			++Np;
+		}
+
+		// Kinetic energy of the particle given by its actual speed
+		E +=   (vd.template getProp<velocity>(p)[0]*vd.template getProp<velocity>(p)[0] +
+				vd.template getProp<velocity>(p)[1]*vd.template getProp<velocity>(p)[1] +
+				vd.template getProp<velocity>(p)[2]*vd.template getProp<velocity>(p)[2]) / 2;
+
+		// Next Particle
+		++it2;
+	}
+
+	return E;
+}
+
+
+#endif /* EXAMPLE_VECTOR_4_REORDER_ENERGY_FORCE_HPP_ */