To specify a single array element as a source element or as a target element of a mapping:
In the Outline view, in the mapping routine area, verify that the selected source element or the selected target element is an array.
In the Properties view, click the Cardinality tab.
In the Cardinality tab:
If a Source array index input field is present, specify the single array element that you want to be the source element.
If a Target array index input field is present, specify the single array element that you want to be the target element.
appears at the left of an input field, you can display a description
of the error by hovering the mouse pointer icon over the error icon.