mat_data_struct f_matpar_H_metal(double H, const std::vector<mat_data_struct> &mat) {
	mat_data_struct matnow;
	int L = 0;
	int R = mat.size() - 1;
	int m;
	while (R - L > 1) {
		m = (R + L) / 2;
		if (H > mat[m].H) {
			L = m;
		}
		else if (H <= mat[m].H) {
			R = m;
		}
	}
	double x = (H - mat[L].H) / double(mat[R].H - mat[L].H);
	matnow.H = H;
	matnow.T = mat[L].T + x * (mat[R].T - mat[L].T);
	matnow.k = mat[L].k + x * (mat[R].k - mat[L].k);
	matnow.rho = mat[L].rho + x * (mat[R].rho - mat[L].rho);
	matnow.cp = mat[L].cp + x * (mat[R].cp - mat[L].cp);
	matnow.mu= mat[L].cp + x * (mat[R].cp - mat[L].cp);
	return matnow;
}