Open Watcom FORTRAN 77 Language Reference

Arrays
3. If the corresponding actual argument is a character array name, character array element or a
substrung character array element which begins at character t of an array with c characters then
the size of the dummy array is INT(( c + 1 − t ) / e) where e is the size of an element of the
dummy array.
If the assumed-size array has dimension n then the product of the first n − 1 dimensions must be less than or
equal to the size of the array as determined by one of the preceding rules. The value of the assumed
dimension is the largest integer such that the product of all of the dimensions is less than or equal to the size
of the dummy array. In the following example, A(4,*) is an assumed-size array declarator.
Example:
DIMENSION B(10)
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CALL SQUARE( B )
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END
SUBROUTINE SQUARE( A )
DIMENSION A(4,*)
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END
By rule 1, the upper bound of the size of A is 10. We now look for the largest integer n such that 4 * n is
less than or equal to 10. Clearly, n is 2. A is therefore a 2-dimensional array with 4 rows and 2 columns.
4.4.4 Allocatable Array Declarator
An allocatable array declarator is one that contains no dimension bound expressions. It is called an
allocatable array declarator because the dimension bounds are specified at run-time in an ALLOCATE
statement.
Example:
DIMENSION A(:), B(:,:)
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ALLOCATE( A(N) )
ALLOCATE( B(0:4,5) )
In the previous example, A(:) is a one-dimensional allocatable array declarator and B(:,:) is a
two-dimensional allocatable array declarator. The first ALLOCATE statement is used to allocate the array A
with bounds 1:N. The second ALLOCATE statement is used to allocate the array B with bounds 0:4 in
the first dimension and 1:5 in the second dimension.
Classifying Array Declarators by Dimension Declarator 163