topic Passing Arguments between Soubroutines - INFINIT RESULT in Intel® Fortran Compiler

Passing Arguments between Soubroutines - INFINIT RESULT

Master_Fortran — Mon, 27 Oct 2014 23:54:03 GMT

Dears,

I don't know what I forgot, but I tryied to reproduce a problem I'm facing, which is resulting in na infinity result of: 1.713457071104324E+124. I don't know what is wrong with it

I'm trying to pass arguments through subroutines. See the code below. Could you help me please?

program principal

double precision x, y, z, k, w

x = 1;

y = 1;

z = 1;

call soma(x,y,z)

call multiplica(k,w)

write(*,*) "The value of w is: ", w

end program

subroutine soma(a,b,c)

double precision, intent(in) :: a,b

double precision, intent(out) :: c

c = a+b

end subroutine

subroutine multiplica(d,e)

double precision, intent(in) :: d

double precision, intent(out) :: e

double precision x,y,z

call soma(x,y,z)

e = z*d

end subroutine

In your multiplica routine,

DavidWhite — Tue, 28 Oct 2014 00:06:28 GMT

In your multiplica routine, the variables x and y have not been initialized.

There is no implicit global sharing of variables in Fortran. You need to share the variables via a module, pass them as arguments, or have the subroutine CONTAINed within the program that declares the variables.

Thank you David, for your

Master_Fortran — Tue, 28 Oct 2014 00:35:33 GMT

Thank you David, for your attention. Sorry, but I'm not undertanding it. See what I did. What's wrong now? The result is: -1.0737418E+08. Thanks again.

module somatorio

implicit none

contains

subroutine soma(a,b,c)

double precision, intent(in) :: a,b
double precision, intent(out) :: c

c = a + b

end subroutine

end module

module multi

use somatorio

implicit none

double precision x,y,z

contains

subroutine multiplica(d,e)

double precision, intent(in) :: d
double precision, intent(out) :: e

call soma(x,y,z)

e = z * d

end subroutine

end module

program principal

use somatorio
use multi

x = 1;
y = 1;
z = 1;

write(*,*) "O valor de e é: ", w

end program

The "result" that you report

mecej4 — Tue, 28 Oct 2014 01:25:00 GMT

The "result" that you report is arbitrary and meaningless. It is just garbage left in memory that is being reported as if it a real number.

To find the place where the error occurs, compile using the /check:uninit compiler option and run. You will see something similar to

forrtl: severe (193): Run-Time Check Failure. The variable \'_PRINCIPAL$W\' is being used without being defined
Image PC Routine Line Source
soma.exe 003E1098 _MAIN__ 50 soma.f90

It might help if you also add 'IMPLICIT NONE' to each subroutine.

The main program USEs the modules containing the subroutines, but since there are no calls to any subroutines in the main program, none of the subroutine code gets executed. Therefore, even if the variable w had been a module variable that was available to the main program, it would still be undefined unless w was initialized.

OK Guys.

Master_Fortran — Tue, 28 Oct 2014 16:25:03 GMT

OK Guys.

Now I see where I was failing.

Thank you all.

Ewerton.