DAXPY para práctica de AC.

daxpy.cc

#include <algorithm>
#include <chrono>
#include <iostream>
#include <iterator>
#include <random>
#include <sstream>
#include <vector>


int main(int argc, char *argv[])
{
	if (argc != 2)
		throw std::invalid_argument("necesito el tamaño del vector");

	size_t n;
	std::istringstream iss(argv[1]);
	iss >> n;
	if(!iss) 
		throw std::invalid_argument("tamaño de vector no válido");

	std::vector<int> x(n);
        std::vector<int> y(n);

	std::default_random_engine generator(n);
	std::uniform_int_distribution<int> distribution(0, 9);
	auto rng = std::bind(distribution, generator);

	for (unsigned int i=0; i<n; i++) {
	    x[i] = rng();
	    y[i] = rng();
	}
	double a = rng();
			  

	auto start = std::chrono::high_resolution_clock::now();

	for (unsigned int i=1; i<=n; i++)
	    y[i]= a*x[i] + y[i];
	
	auto stop = std::chrono::high_resolution_clock::now();

	std::cout << std::chrono::duration_cast<std::chrono::nanoseconds>(stop - start).count() << "ns" << std::endl;

	// Imprime para evitar que la optimización borre el código intermedio
	if (n < 10)
	    std::cerr << "c = " << x[1] << y[1] << x[n-1] << y[n-1] << std::endl;
}