a(d[,d]...) a is the name of the array d specifies the bounds of the array in the form:
[dl:]du dl is the lower bound
du is the upper bound
Subscripts
A subscript qualifies an array name. A subscript is a list of
expressions, called subscript expressions, enclosed in parentheses,
that determine which element in the array is referred to. The
subscript is appended to the array name it qualifies. A subscript
has the form:
(s[,s]...) s is a subscript expression
A one-dimensional array is stored with its first element in the first storage location and its last element in the last storage location of the sequence. A multidimensional array is stored so that the leftmost subscripts vary most rapidly.