theta = [0 0.5 -1 1]; x[1][1] = [1 2 0 0]; x[1][2] = [1 1 0 0]; x[1][3] = [1 0 0 1]; x[2][1] = [1 0 -1 0]; x[2][2] = [1 0 0 0]; x[2][3] = [1 -1 0.5 0]; x[3][1] = [1 1 0 0]; x[3][2] = [1 -1 2 -2]; x[3][3] = [1 0 5 -1];