Glossary A

absolute pathname: On Windows, Tru64 UNIX, and Linux systems, a directory path specified in fixed relationship to the root directory. On Tru64 UNIX and Linux systems, the first character is a slash (/). On Windows systems, the first character is a backslash (\).
active screen buffer: The screen buffer that is currently displayed in a console's window.
active window: A top-level window of the application with which the user is working. The Windows system identifies the active window by highlighting its title bar and border.
actual argument: An expression, variable, procedure, or alternate return specifier that is specified in a subroutine or function reference. The value is passed from the calling program unit to a subprogram.
adjustable array: An explicit-shape array that is a dummy argument to a subprogram. The term is from FORTRAN-77. See also explicit-shape array.
aggregate reference: A reference to a record structure field.
allocatable array: A named array that has the ALLOCATABLE attribute. Once space has been allocated for this type of array, the array has a shape and can be defined (and redefined) or referenced. It is an error to allocate an allocatable array that is currently allocated.
allocation status: Indicates whether an allocatable array or pointer is allocated. An allocation status is one of: allocated, deallocated, or undefined. An undefined allocation status means an array can no longer be referenced, defined, allocated, or deallocated. See also association status.
alphanumeric: Pertaining to letters and digits.
alternate key: On OpenVMS systems, an optional key within the data records in an indexed file, which can be used to build an alternate index.
alternate return: A subroutine argument that permits control to branch immediately to some position other than the statement following the call. The actual argument in an alternate return is the statement label to which control should be transferred. (An alternate return is an obsolescent feature in Fortran 90.)
ANSI: The American National Standards Institute. An organization through which accredited organizations create and maintain voluntary industry standards.
argument: See actual argument and dummy argument.
argument association: The relationship (or "matching up") between an actual argument and dummy argument during the execution of a procedure reference.
argument keyword: The name of a dummy (formal) argument. It can be used in a procedure reference before the equals sign [keyword = actual argument] provided the procedure has an explicit interface. This association allows actual arguments to appear in any order.

Argument keywords are supplied for many of the intrinsic procedures.
array: A set of scalar data that all have the same type and kind type parameters. An array can be referenced by element (using a subscript), by section (using a section subscript list), or as a whole. An array has a rank (up to 7), bounds, size, and a shape.

An individual array element is a scalar object. An array section, which is itself an array, is a subset of the entire array.

Contrast with scalar. See also bounds, conformable, shape, size, whole array, and zero-sized array.
array constructor: A mechanism used to specify a sequence of scalar values that produce a rank-one array.

To construct an array of rank greater than one, you must apply the RESHAPE intrinsic function to the array constructor.
array element: A scalar (individual) item in an array. An array element is identified by the array name followed by one or more subscripts in parentheses, indicating the element's position in the array. For example, B(3) or A(2,5).
array pointer: A pointer to an array. See also array and pointer.
array section: A subobject (or portion) of an array. It consists of the set of array elements or substrings of this set. The set (or section subscript list) is specified by subscripts, subscript triplets, and vector subscripts. If the set does not contain at least one subscript triplet or vector subscript, the reference indicates an array element, not an array.
array specification: A program statement specifying an array name and the number of dimensions the array contains (its rank). An array specification can appear in a DIMENSION or COMMON statement, or in a type declaration statement.
ASCII: The American Standard Code for Information Interchange. A 7-bit character encoding scheme associating an integer from 0 through 127 with 128 characters.
assignment: A statement in the form variable = expression. The statement assigns (stores) the value of an expression on the right of an equal sign to the storage location of the variable to the left of the equal sign. In the case of Fortran 95/90 pointers, the storage location is assigned, not the pointer itself.
association: The mechanism that permits an entity to be referenced by different names in the same or in different scoping units. The principal kinds of association are argument association, host association, pointer association, storage association, and use association.
association status: Indicates whether or not a pointer is associated with a target. An association status is one of: undefined, associated, or disassociated. An undefined association status means a pointer can no longer be referenced, defined, or deallocated. An undefined pointer can, however, be allocated, nullified, or pointer assigned to a new target. See also allocation status.
assumed-length character argument: A dummy argument that assumes the length attribute of the corresponding actual argument. An asterisk (*) specifies the length of the dummy character argument.
assumed-shape array: A dummy argument array that assumes the shape of its associated actual argument array.
assumed-size array: A dummy array that takes the size of the actual argument passed to it. The rank, extents, and bounds of the dummy array are specified in its declaration, except for the upper bound (which is specified by a *) and the extent of the last dimension.
attribute: A property of a data object that can be specified in a type declaration statement. These properties determine how the data object can be used in a program.

Most attributes can be alternatively specified in statements. For example, the DIMENSION statement has the same meaning as the DIMENSION attribute appearing in a type declaration statement.
automatic array: An explicit-shape array that is a local variable in a subprogram. It is not a dummy argument, and has bounds that are nonconstant specification expressions. The bounds (and shape) are determined at entry to the procedure by evaluating the bounds expressions. See also automatic object.
automatic object: A local data object that is created upon entry to a subprogram and disappears when the execution of the subprogram is completed. There are two kinds of automatic objects: arrays (of any data type) and objects of type CHARACTER. Automatic objects cannot be saved or initialized.

An automatic object is not a dummy argument, but is declared with a specification expression that is not a constant expression. The specification expression can be the bounds of the array or the length of the character object.