A vector subscript may contain more elements than the size of that array dimension. In this case there are duplicate values, since all of the values must be within the array dimension range. Indeed, subscript values may be duplicated in a vector subscript even if the size of the vector is less than the array dimension (the only requirement is that the subscript values must be within range). Both of these cases are illustrated in the following example, which specifies a 7x4 section from the elements of .
Note that rows one and five of this section are identical, as are rows three and six and columns two and three. Many elements of therefore appear twice in this array section and two elements, and , each appear four times. Array sections with multiple appearances of a given parent array element are perfectly legitimate array operands in array expressions, but such sections must not appear on the left hand side of array assignments.