Purpose
Accesses the value of a specified element in an ARRAY data type value.
Syntax
 array_expression
 An expression that evaluates to an ARRAY data type.
 index_value

Index to the element in the array whose value you want to access.
For a 1D ARRAY type, index_value must be a positive integer in the range from 1 to n, where n is the declared size of the ARRAY type.
For an nD ARRAY type, index_value must be a positive or negative integer in the range from m to n, where m is the declared lower bound of a dimension of the array, and n is the declared upper bound.