123   PetscReal **au, dx, dy, x, y;  in FormExactSolution()  local
126   dx = 4.0 / (PetscReal)(info->mx - 1);  in FormExactSolution()
132       x        = -2.0 + i * dx;  in FormExactSolution()
145   PetscReal   **aXl, dx, dy, x, y;  in FormBounds()  local
150   dx = 4.0 / (PetscReal)(info.mx - 1);  in FormBounds()
156       x         = -2.0 + i * dx;  in FormBounds()
168   PetscReal dx, dy, x, y, ue, un, us, uw;  in FormFunctionLocal()  local
171   dx = 4.0 / (PetscReal)(info->mx - 1);  in FormFunctionLocal()
176       x = -2.0 + i * dx;  in FormFunctionLocal()
180         uw       = (i - 1 == 0) ? u_exact(x - dx, y) : au[j][i - 1];  in FormFunctionLocal()
181         ue       = (i + 1 == info->mx - 1) ? u_exact(x + dx, y) : au[j][i + 1];  in FormFunctionLocal()
184         af[j][i] = -(dy / dx) * (uw - 2.0 * au[j][i] + ue) - (dx / dy) * (us - 2.0 * au[j][i] + un);  in FormFunctionLocal()
196   PetscReal  v[5], dx, dy, oxx, oyy;  in FormJacobianLocal()  local
199   dx  = 4.0 / (PetscReal)(info->mx - 1);  in FormJacobianLocal()
201   oxx = dy / dx;  in FormJacobianLocal()
202   oyy = dx / dy;  in FormJacobianLocal()