gistfile1.cpp

/*
 * Patrick Lerner
 * Manual Spari
 */

#include <iostream>
#include <cmath>

template <typename T, int N>
class Vector
{
	private:
		T *data;
	public:
		Vector() {
			this->data = new T[N];
		};

		T& operator[](int index) {
			return data[index];
		};

		Vector<T, N> operator+(Vector<T, N> &otherOne) {
			Vector<T, N> result;
			for (int i = 0; i < N; i++)
				result[i] = data[i] + otherOne[i];
			return result;
		};

		Vector<T, N> operator*(float otherOne) {
			Vector<T, N> result;
			// scalar multiplication
			for (int i = 0; i < N; i++)
				result[i] = data[i] * otherOne;
			return result;
		};

		T operator*(Vector<T, N> &otherOne) {
			T sum = 0;
			// scalar product
			for (int i = 0; i < N; i++)
				sum += data[i] * otherOne[i];
			return sum;
		};

		void print() {
			for (int i = 0; i < N; i++)
				std::cout << data[i] << (i < N-1 ? "\t" : "\n");
		};

		float length() {
			// length is squareroot of the sum of
			// all the squares of the entries
			float powersum = 0;
			for (int i = 0; i < N; i++)
				powersum += pow(data[i], 2);
			return sqrt(powersum);
		};
};

int main()
{
	typedef Vector<float, 3> Vector;
	Vector f, g;
	f[0] = 1.0f; f[1] = 2.0f; f[2] = 3.0f;
	g[0] = 3.0f; g[1] = 2.0f; g[2] = 1.0f;

	Vector h = f + g;
	
	Vector m = g * 3.0f;

	f.print();		// 1  2  3
	g.print();		// 3  2  1
	h.print();		// 4  4  4
	m.print();		// 9  6  3
	std::cout << (f * g) << '\n'			// 10  
	          << f.length() << std::endl;	// 3.74166

	return 0;
}