void CloverLeaf2x2(Lattice& lattice, Matrix& pl, int* pos, int mu, int nu)
{
Matrix P0,P1,P2,P3;
// 1x2 size
P0.ZeroMatrix();
P1.ZeroMatrix();
P2.ZeroMatrix();
P3.ZeroMatrix();
// each direction could be {0,1,2,3,4,5,6,7} coresponding to
// the directions {n_x, n_y, n_z, n_t, -n_x, -n_y, -n_z, -n_t}
int dirs0[8]={mu,mu, nu, nu, mu+4,mu+4, nu+4, nu+4};
lattice.PathOrdProdPlus(P0, pos, dirs0, 8);
int dirs1[8]={nu+4, nu+4, mu+4, mu+4, nu, nu, mu,mu };
lattice.PathOrdProdPlus(P1, pos, dirs1, 8);
int dirs2[8]={nu, nu, mu+4, mu+4, nu+4, nu+4, mu, mu };
lattice.PathOrdProdPlus(P2, pos, dirs2, 8);
int dirs3[8]={mu,mu, nu+4, nu+4, mu+4, mu+4, nu, nu };
lattice.PathOrdProdPlus(P3, pos, dirs3, 8);
P0 -= P1;
P0 += P2;
P0 -= P3;
P0 *= 1.0/16;
moveMem((Float*) &pl,(Float*) &P0, 18 * sizeof(Float) );
}
