Fortran 可分配数组
示例
数组可以具有可分配的属性:
! One dimensional allocatable array integer, dimension(:), allocatable :: foo ! Two dimensional allocatable array real, dimension(:,:), allocatable :: bar
这将声明变量,但不会为其分配任何空间。
! We can specify the bounds as usual allocate(foo(3:5)) ! It is an error to allocate an array twice ! so check it has not been allocated first if (.not. allocated(foo)) then allocate(bar(10, 2)) end if
一旦不再需要一个变量,就可以释放它:
deallocate(foo)
如果由于某种原因allocate语句失败,程序将停止。如果通过stat关键字检查状态,可以防止这种情况:
real, dimension(:), allocatable :: geese integer :: status allocate(geese(17), stat=status) if (stat /= 0) then print*, "Something went wrong trying to allocate 'geese'" stop 1 end if
该deallocate语句也具有stat关键字:
deallocate (geese, stat=status)
status是一个整数变量,如果分配或取消分配成功,则值为0。