#include <cassert>
#include <cmath>

#include "matrix.hpp"

void test_create_symmetric_tridiagonal() {
    double tol = 10e-8;
    double diff;
    int N = 6;
    double h = 1./(double) (N+1);
    double a = -1. / (h*h), d = 2. / (h*h);

    arma::mat A = create_symmetric_tridiagonal(N, a, d);

    arma::vec eigval;
    arma::mat eigvec;

    arma::eig_sym(eigval, eigvec, A);

    for (int i=0; i < N; i++) {
        diff = eigval(i) - (d + 2.*a*std::cos(((i+1.)*M_PI)/(N+1.)));
        assert(std::abs(diff) < tol); 
    }
}

void test_max_off_diag_symmetric() {

}

int main() {

    test_create_symmetric_tridiagonal();

    return 0;
}