22  t2s_1(
i, 
j) = t2s_2(
i, 
j) + (t1_2(
j) ^ t1_2(
i));
 
   23  test_for_zero(t2s_1(0, 0) - (t2s_2(0, 0) + t1_2(0) * t1_2(0)),
 
   24                "T2s(i,j)+T2s(j,i)(0,0)");
 
   25  test_for_zero(t2s_1(0, 1) - (t2s_2(0, 1) + t1_2(1) * t1_2(0)),
 
   26                "T2s(i,j)+T2s(j,i)(0,1)");
 
   27  test_for_zero(t2s_1(0, 2) - (t2s_2(0, 2) + t1_2(2) * t1_2(0)),
 
   28                "T2s(i,j)+T2s(j,i)(0,2)");
 
   29  test_for_zero(t2s_1(1, 1) - (t2s_2(1, 1) + t1_2(1) * t1_2(1)),
 
   30                "T2s(i,j)+T2s(j,i)(1,1)");
 
   31  test_for_zero(t2s_1(1, 2) - (t2s_2(1, 2) + t1_2(2) * t1_2(1)),
 
   32                "T2s(i,j)+T2s(j,i)(1,2)");
 
   33  test_for_zero(t2s_1(2, 2) - (t2s_2(2, 2) + t1_2(2) * t1_2(2)),
 
   34                "T2s(i,j)+T2s(j,i)(2,2)");
 
 
void test_T2s_12(const Tensor1< double, 3 > &t1_2, Tensor2_symmetric< double, 3 > &t2s_1, const Tensor2_symmetric< double, 3 > &t2s_2)