Forgot Fortran

[daveask]

Hi,

I knew Fortran long time ago but forgot all now. Can you correct the folloing program for me?

Thank you in advance.

PROGRAM Hello

REAL a(2,2)
a = (/1.0,2.0,3.0,4.0/)
CALL Test(a)
print*,a(1,1)

CONTAINS
SUBROUTINE Test(a)
REAL a(2,2)
a(1,1)=a(1,1)+9.0
END SUBROUTINE Test

END PROGRAM Hello

 

[daveask]

Why we need to put subroutine inside the "main" program?

 

[PAndersen]

C ThePROGRAM Hello
REAL a(2,2)
C a = (/1.0,2.0,3.0,4.0/) instead try :
DATA A /1.0,2.0,3.0,4.0/
CALL Test(a)
print*,a(1,1)
C CONTAINS
END
SUBROUTINE Test(a)
REAL a(2,2)
a(1,1)=a(1,1)+9.0
RETURN
END

The subroutine can be compiled as a separate program and linked to the main program before execution.

 

[daveask]

PAndersen,

Thank you for your help.
>C a = (/1.0,2.0,3.0,4.0/) instead try :
> DATA A /1.0,2.0,3.0,4.0/
Why not use a = (/1.0,2.0,3.0,4.0/)? I forget DATA already.....but are you talking Fortran77 ?

 

[PAndersen]

If a = (/1.0,2.0,3.0,4.0/) gives no compilation error, use it. The DATA statement is for FTN77 and older.

 

[daveask]

Thanks a lot for your suggestion.