Tests of the choice of the bounds of integral (14). The x and y coordinates of the force are plotted, respectively, in the top and bottom panels, for various choices of the integration range [ − q_max, q_max] with q_max ranging from L/2 to 20L/2, as indicated in the upper-left panel. From left to right, we consider Q1D-2SIN, ANI-2SIN, Q1D-3SIN, and ANI-3SIN initial conditions. In the top panels, various values of y are considered, as indicated in the second panel of the top row, while the bottom panels only assume x = 0 since other values of x would not lead to significantly different results. We also set z = 0 in the 3D cases considered in the two top-right and two bottom-right panels. Note that the output time chosen in this figure is the same as in Fig. 5. We see that all the curves corresponding to different values of q_max are superimposed on each other, except for q_max = L/2 for the Q1D cases.