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Declares a variable to be an array. SyntaxA
type declaration statement with the DIMENSION attribute is: type, DIMENSION ( array-spec ) [[, attrib-list ]::] entity-list |
- type
is a valid type specification (INTEGER, REAL, LOGICAL, CHARACTER, TYPE( type-name ), etc.). - array-spec
is one of the following: - explicit-shape-spec
is [lower-bound :] upper-bound - lower-bound, upper-bound
are specification expressions. - assumed-shape-spec
is - deferred-shape-spec
is - assumed-size-spec
is [explicit-shape-spec-list ,] [lower-bound :] * That is, assumed-size-spec is explicit-shape-spec-list with the final upper bound specified as *. - attrib-list
is a comma-separated list of attributes including DIMENSION and optionally those attributes compatible with
it, namely: Table 10-7 Title not available (DIMENSION (statement and attribute)) ALLOCATABLE | PARAMETER | PUBLIC | INTENT | POINTER | SAVE | OPTIONAL | PRIVATE | TARGET |
- entity-list
is object-name[(array-spec)] If (array-spec) is present, it overrides the (array-spec) given with the DIMENSION keyword in attribute-list; see the example below.
The syntax of the DIMENSION statement is: DIMENSION [::] array-name (array-spec)
[, array-name (array-spec) ]... |
DescriptionAn array consists
of a set of objects called the array elements, all of the same type
and type parameters, arranged in a pattern involving columns, and
possibly rows, planes, and higher dimensioned configurations. The
type of the array elements may be intrinsic or user-defined. In
HP Fortran, an array may have up to seven dimensions. The number
of dimensions is called the rank of the array and is fixed when
the array is declared. Each dimension has an extent that is the
size in that dimension (upper bound minus lower bound plus one).
The size of an array is the product of its extents. The shape of
an array is the vector of its extents in each dimension. Two arrays
that have the same shape are said to be conformable. It is not necessary for the keyword DIMENSION to appear in the declaration of a variable to give
it the DIMENSION attribute. This attribute, as well as the rank,
and possibly the extents and the bounds of an array, may be specified
in the entity declaration part of any of the following statements: The array-spec (see Syntax, above) determines
the category of the array being declared. “Array
declarations”, describes these categories as: Examples! These 2 declaration statements are equivalent.
REAL a (20,2), b (20,2), c (20,2)
REAL, DIMENSION (20,2) :: a, b, c
DIMENSION x(100), y(100) ! x and y are 1-dimensional
! lower bounds specified for jj (if not given, they default to 1)
INTEGER jj (0:100, -1:1)
! l is a 4-dimensional, allocatable, deferred shape logical array
LOGICAL l
ALLOCATABLE l(:,:,:,:)
COMPLEX s ! s has explicit shape and
TARGET :: s(10,2) ! the target attribute
DOUBLE PRECISION d
! d has 5 dimensions and is declared in common
COMMON /stuff/ d(2,3,5,9,8)
! arr1 is an adjustable array, arr2 an automatic array
SUBROUTINE calc(arr1, ib1, ib2)
REAL, DIMENSION (ib1, ib2) :: arr1, arr2
! arr3 is a deferred-shape array with the pointer attribute
REAL, POINTER, DIMENSION(:,:) :: arr3
! all three arrays have explicit shape; array specifier (10,10)
! overrides specifier (10,20) for tb declaration only
LOGICAL, DIMENSION(10,20) :: ta, tb(10,10), tc
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Related statementsALLOCATABLE, COMMON, POINTER, TARGET, TYPE, and the type declaration statements Related conceptsFor related information, see the following: The following array-inquiry intrinsics described
in Chapter 11:
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