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─────DIMENSION──────────────────────────────────────────────────────────────
 
     Action
 
     Declares a variable as an array and specifies its dimensions and
     bounds.
 
     Syntax
 
     DIMENSION array [ [attrs] ] ({ [lower:] upper | : }
     [,{[lower:]upper | :}... ])
 
     Parameter          Description
 
     array              Array name. Separate multiple arrays with commas.
 
     [attrs]            A list of attributes separated by commas. Valid
                        attributes are: ALIAS, ALLOCATABLE, C, EXTERN,
                        FAR, HUGE, NEAR, PASCAL, REFERENCE, VALUE.
 
     lower              Lower dimension bound. Default is one.
 
     upper              Upper dimension bound. Greater than or equal to
                        <lower> bound.
 
     Remarks
 
     You can use any of the following as dimension bounds:
 
     Bound                      Description
 
     Arithmetic constant        Produces an array with a constant size.
                                The arithmetic value is truncated to an
                                integer.
 
     Nonarray-integer formal    Produces an adjustable-size array with
     argument or nonarray-      dimensions equal to the initial value
     integer variable in a      of the variable upon entry to the
     common block in the same   subprogram.
     program unit
 
     An arithmetic              Produces an adjustable-size array with
     expression                 dimensions equal to the expression. The
                                expression is truncated to an integer.
                                Expressions cannot contain references
                                to functions or array elements.
 
     An asterisk (*)            Produces an assumed-size array in a
                                subprogram with dimension size the same
                                as the array in the calling program. Can
                                only be used as <upper> in the last
                                dimension of <array>. If <upper> is
                                an asterisk, then array is an "assumed-
                                size" array. The following DIMENSION
                                statement defines an assumed-size array
                                in a subprogram:
 
                                    DIMENSION data (19,*)
 
                               At execution time, the array data is
                               given the size of the corresponding
                               array in the calling program.
 
     Within noncharacter arrays, all elements begin on even-byte
     (word) addresses. Within character arrays (and arrays of
     INTEGER*1 or LOGICAL*1 variables), elements always begin at the
     next available byte (odd or even).
 
     All adjustable- and assumed-size arrays, as well as the bounds
     for adjustable-size arrays, must be formal arguments to the
     program unit in which they appear. Allocatable arrays must not be
     formal arguments.
 
     Examples
 
     The following program dimensions two arrays:
 
           DIMENSION a(2,3), v(10)
           CALL Subr (a, 2, v)
           .
           .
           .
           END
 
           SUBROUTINE Subr (matrix, rows, vector)
           REAL MATRIX, VECTOR
           INTEGER ROWS
           DIMENSION MATRIX (ROWS,*), VECTOR (10),
        +  LOCAL (2,4,8)
           MATRIX (1,1) = VECTOR (5)
           .
           .
           .
           END
 
     The following program uses assumed- and adjustable-size arrays:
 
           REAL     magnitude, minimum
           INTEGER  vecs, space, vec
 
     C     Array data values are assigned in column-major order
           DIMENSION  vecs(3, 4)
           DATA       vecs /1,1,1,2, 1,0,3,4, 7,-2,2,1 /
 
     C     Find minimum magnitude
           minimum = 1E10
           DO 100 vec = 1, 4
 
     C     Call the function magnitude to calculate the magnitude of
     C     vector vec.
              minimum = AMIN1(minimum, magnitude(vecs, 3, vec))
       100 CONTINUE
 
           WRITE (*, 110) minimum
       110 FORMAT (' Vector closest to origin has a magnitude of',
          +          F12.6)
           END
 
     C     Function returns the magnitude of the j-th column vec in a
     C     matrix. Note that, because of the assumed-size array, the
     C     subroutine does not need to know the number of columns in
     C     the matrix. It only requires that the specified column
     C     vector be a valid column in the matrix. The number of rows
     C     must be passed so the function can do the sum.
 
           REAL FUNCTION Magnitude (matrix, rows, j)
 
           REAL       sum
           INTEGER    matrix, rows, i, j
           DIMENSION  matrix (rows,*)
 
           sum = 0.0
           DO 100 i = 1, rows
           sum = sum + matrix(i,j)**2
           100  CONTINUE
           magnitude = SQRT (sum)
           END
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