Working With Arrays

demo% dbx a.out
Reading symbolic information…
(dbx) list 1,25
    1           DIMENSION IARR(4,4)
    2           DO 90 I = 1,4
    3                   DO 20 J = 1,4
    4                           IARR(I,J) = (I*10) + J
    5   20              CONTINUE
    6   90      CONTINUE
    7           END
(dbx)  stop at 7
(1) stop at "Arraysdbx.f":7
(dbx) run
Running: a.out
stopped in MAIN at line 7 in file "Arraysdbx.f"
    7           END
(dbx) print IARR
iarr =
    (1,1) 11
    (2,1) 21
    (3,1) 31
    (4,1) 41
    (1,2) 12
    (2,2) 22
    (3,2) 32
    (4,2) 42
    (1,3) 13
    (2,3) 23
    (3,3) 33
    (4,3) 43
    (1,4) 14
    (2,4) 24
    (3,4) 34
    (4,4) 44
(dbx) print IARR(2,3)
    iarr(2, 3) = 23  - Order of user-specified subscripts ok
(dbx) quit

demo% f95 -g Alloc.f95
  demo% dbx a.out
  (dbx) list 1,99
      1   PROGRAM TestAllocate
      2   INTEGER n, status
      3   INTEGER, ALLOCATABLE :: buffer(:)
      4           PRINT *, ’Size?’
      5           READ *, n
      6           ALLOCATE( buffer(n), STAT=status )
      7           IF ( status /= 0 ) STOP ’cannot allocate buffer’
      8           buffer(n) = n
      9           PRINT *, buffer(n)
     10           DEALLOCATE( buffer, STAT=status)
     11   END
(dbx) stop at 6
 (2) stop at "alloc.f95":6
 (dbx) stop at 9
 (3) stop at "alloc.f95":9
 (dbx) run
 Running: a.out
 (process id 10749)
  Size?
 1000
Unknown size at line 6
 stopped in main at line 6 in file "alloc.f95"
     6           ALLOCATE( buffer(n), STAT=status )
 (dbx) whatis buffer
 integer*4 , allocatable::buffer(:)
 (dbx) next
 continuing
 stopped in main at line 7 in file "alloc.f95"
     7           IF ( status /= 0 ) STOP ’cannot allocate buffer’
 (dbx) whatis buffer
 integer*4 buffer(1:1000)
Known size at line 9
 (dbx) cont
 stopped in main at line 9 in file "alloc.f95"
     9           PRINT *, buffer(n)
 (dbx) print n
buffer(1000) holds 1000
 n = 1000
 (dbx) print buffer(n)
 buffer(n) = 1000