Intel Fortran Language Reference - NCI National Facility

Data Types, Constants, and Variables 3
When the length of the constant is greater than the length implied by the data type, the
constant is truncated on the right. If any characters other than blank characters are truncated,
an error occurs.
Each Hollerith character occupies one byte of memory.
See Also
Variables
The Compiler Options reference for details on compiler options
A variable is a data object whose value can be changed at any point in a program. A variable can
be any of the following:
• A scalar
A scalar is a single object that has a single value; it can be of any intrinsic or derived
(user-defined) type.
• An array
An array is a collection of scalar elements of any intrinsic or derived type. All elements must
have the same type and kind parameters.
• A subobject designator
A subobject is part of an object. The following are subobjects:
An array element
An array section
A structure component
A character substring
For example, B(3) is a subobject (array element) designator for array B. A subobject cannot
be a variable if its parent object is a constant.
The name of a variable is associated with a single storage location.
Variables are classified by data type, as constants are. The data type of a variable indicates the type
of data it contains, including its precision, and implies its storage requirements. When data of any
type is assigned to a variable, it is converted to the data type of the variable (if necessary).
A variable is defined when you give it a value. A variable can be defined before program
execution by a DATA statement or a type declaration statement. During program execution,
variables can be defined or redefined in assignment statements and input statements, or undefined
(for example, if an I/O error occurs). When a variable is undefined, its value is unpredictable.
When a variable becomes undefined, all variables associated by storage association also become
undefined.
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