On the point selection page you specify the number of points and their location.
If you chose to extract the components as scalars, the points are extracted in the coordinates (j,k) you specify in the list on this page.
If you chose to extract items as vectors, the points are not extracted in the exact coordinate that is specified in the list, but from a location placed half a grid cell down and to the left, respectively, see image below. If you for instance extract the magnitude and direction in a point with the coordinates (j,k), you will get the magnitude and direction based on model results in the points P(j,k) and Q(j,k) as illustrated below.
Figure 3.2 Definition of point position in extraction of vector items
