形状引継ぎ配列

主プログラムで宣言した配列の大きさを、副プログラム側に引き継ぐ。

副プログラム側では、配列の大きさを宣言する必要がなくなる。

ただし、主プログラム側で、interface文を使う必要がある。

プログラム例

主プログラム：test_cal_sum.f90

program test_cal_sum

! Description:

! Author: am

! Host: aofd30

! Directory: /work2/am/teaching/21.Fortran/01.interface

! Revision history:

!  2011-05-09 08:42

!    Initial Version

!  use

!  implicit none

  interface

    subroutine cal_sum(a, s)

      real,intent(in) :: a(:)

      real,intent(out) :: s

    end subroutine cal_sum

  end interface

  integer,parameter :: n=10

  real a(n)

  write(*,'(a)')'Program test_cal_sum starts.'

!  write(*,*)''

  do i=1,n

    a(i)=float(i)

  enddo !i

  call cal_sum(a,s)

  print *,'i, a(i)'

  do i=1,n

    print *,i,a(i)

  enddo !i

  print *

  print *,'sum= ',s

  print *

  write(*,'(a)')'Done program test_cal_sum.'

  write(*,*)

end program test_cal_sum

副プログラム：cal_sum.f90

subroutine cal_sum(a,s)

! Description:

! Author: am

! Host: aofd30

! Directory: /work2/am/teaching/21.Fortran/01.interface

! Revision history:

!  2011-05-09 08:42

!    Initial Version

  real,intent(in) :: a(:)

  real,intent(out) :: s

  write(*,'(a)')'Subroutine: cal_sum'

  write(*,*)''

  n=size(a,1)

  print *,'n= ',n

  do i=1,n

    s=s+a(i)

  enddo !i

  write(*,'(a)')'Done subroutine cal_sum.'

  write(*,*)

end subroutine cal_sum

使用例

コンパイル

makefile:

$ make

make: Warning: File `makefile' has modification time 4.3e+02 s in the future

if [ ! -d ../obj ]; then \

mkdir -p ../obj ; \

ifort -c -module ../obj -c -o ../obj/cal_sum.o cal_sum.f90

ifort -c -module ../obj -c -o ../obj/test_cal_sum.o test_cal_sum.f90

ifort -o test_cal_sum ../obj/cal_sum.o ../obj/test_cal_sum.o -module ../obj

make: warning: Clock skew detected. Your build may be incomplete.

real 0m0.097s

user 0m0.054s

sys 0m0.041s

実行例

$ ./test_cal_sum

Program test_cal_sum starts.

Subroutine: cal_sum

n= 10

Done subroutine cal_sum.

i, a(i)

1 1.000000

2 2.000000

3 3.000000

4 4.000000

5 5.000000

6 6.000000

7 7.000000

8 8.000000

9 9.000000

10 10.00000

sum= 55.00000

Done program test_cal_sum.