net.cpp

#include <xtensor/xarray.hpp>
#include <xtensor/xrandom.hpp>
#include <xtensor/xio.hpp>
#include <xtensor/xindexview.hpp>
#include <xtensor-blas/xlinalg.hpp>

#include <iostream>
#include <vector>
using namespace std;

auto activate = [](auto x, bool diriv = false) -> decltype(x)
{
	if(diriv)
		return x*(1-x);
	return 1/(1+xt::exp(x));
};

int main()
{
	xt::xarray<float> x({{0,1},{1,1},{0,0,},{1,0}});
	xt::xarray<float> y({{0,1,0,0}});
	y = xt::transpose(y);

	xt::xarray<float> syn0 = 2 * xt::random::rand<float>({2,3}) - 1;
	xt::xarray<float> syn1 = 2 * xt::random::rand<float>({3,1}) - 1;

	//for(int i=0;i<10000;i++)
	{
		//Forward prpoergate
		for(unsigned int j=0;j<4;j++)
		{
			xt::xarray<float> l0 = xt::index_view(x, {{j,0},{j,1}});
			cout << l0 << endl;
			xt::xarray<float> l1 = activate(xt::linalg::dot(l0,syn0));
			xt::xarray<float> l2 = activate(xt::linalg::dot(l1,syn1));

			xt::xarray<float> target = xt::index_view(y, {{j,0},{j,0}});

			xt::xarray<float> l2Error = target - l2;
			xt::xarray<float> l2Delta = l2Error * activate(l2,true);
			xt::xarray<float> l1Error = xt::linalg::dot(l2, xt::transpose(syn1));
			xt::xarray<float> l1Delta = l1Error * activate(l1,true);
                        
                        //Unn then....?

			syn1 += xt::linalg::dot(l2Error, xt::transpose(syn2));

			cout << l1Delta << endl;
		}
		//if(i%1000 == 0)

	}
}