COEFF(-2,-2) = factor * coeff_dxx_m2_m2;
COEFF(-1,-2) = factor * coeff_dxx_m1_m2;
COEFF(0,-2) = factor * coeff_dxx_0_m2;
COEFF(1,-2) = factor * coeff_dxx_p1_m2;
COEFF(2,-2) = factor * coeff_dxx_p2_m2;
COEFF(-2,-1) = factor * coeff_dxx_m2_m1;
COEFF(-1,-1) = factor * coeff_dxx_m1_m1;
COEFF(0,-1) = factor * coeff_dxx_0_m1;
COEFF(1,-1) = factor * coeff_dxx_p1_m1;
COEFF(2,-1) = factor * coeff_dxx_p2_m1;
COEFF(-2,0) = factor * coeff_dxx_m2_0;
COEFF(-1,0) = factor * coeff_dxx_m1_0;
COEFF(0,0) = factor * coeff_dxx_0_0;
COEFF(1,0) = factor * coeff_dxx_p1_0;
COEFF(2,0) = factor * coeff_dxx_p2_0;
COEFF(-2,1) = factor * coeff_dxx_m2_p1;
COEFF(-1,1) = factor * coeff_dxx_m1_p1;
COEFF(0,1) = factor * coeff_dxx_0_p1;
COEFF(1,1) = factor * coeff_dxx_p1_p1;
COEFF(2,1) = factor * coeff_dxx_p2_p1;
COEFF(-2,2) = factor * coeff_dxx_m2_p2;
COEFF(-1,2) = factor * coeff_dxx_m1_p2;
COEFF(0,2) = factor * coeff_dxx_0_p2;
COEFF(1,2) = factor * coeff_dxx_p1_p2;
COEFF(2,2) = factor * coeff_dxx_p2_p2;