What are the ways to pass a set of variable values through the subroutine to a function without common block?

Question

I do not want to use common blocks in my program. My main program calls a subroutine which calls a function. The function needs variables from the subroutine.

What a

Answer 1

So, basically you could solve this with something along these lines:

SUBROUTINE CONDACT(i,j, iab11,iab22,xx2,yy2,zz2,b1,c1,f1,g1,h1,d1,b2,c2,f2,g2,h2,p2,q2,r2,d2,res)
  !declaration to all those parameters and res
  res = f(x)
END SUBROUTINE CONDACT

function f(x,iab11,iab22,xx2,yy2,zz2,b1,c1,f1,g1,h1,d1,b2,c2,f2,g2,h2,p2,q2,r2,d2)
!declaration to all those parameters
end function f

program
  ...

  call CONDAT(i,j,iab11,iab22,xx2,yy2,zz2,b1,c1,f1,g1,h1,d1,b2,c2,f2,g2,h2,p2,q2,r2,d2,res)

end program

That is, just passing the parameters through. It is strongly encouraged to use modules, see Alexander McFarlane's answer, though it is not required. Alexander McFarlane shows how to pass f as an argument to the subroutine, such that you could use different functions in the subroutine, but your code does not seem to require this.

Now, this is an awful long list of parameters, and you probably do not want to carry those around all the time. The usual approach to deal with this, is to put those parameters into a derived datatype and then just passing this around. Like this:

!> A module implementing ellip related stuff.
module ellip_module

  implicit none

  type ellip_type
    !whatever datatypes these need to be...
    integer :: b1,c1,f1,g1,h1,d1,b2,c2,f2,g2,h2,p2,q2,r2,d2
  end type
end module ellip_module


!> A module implementing condact related stuff.
module condact_module
  use ellip_module ! Make use of the ellip module to have the type available

  implicit none

  type condact_type
    !whatever datatypes these need to be...
    integer :: iab11,iab22,xx2,yy2,zz2
  end type

  contains

  subroutine condact(i,j, con, ellip, res)
     integer :: i,j
     type(condact_type) :: con
     type(ellip_type) :: ellip
     real :: res

     real :: x
     res = f(x, con, ellip)
  end subroutine condact

  function f(x, con, ellip) result(res)
    real :: x
    real :: res
    type(condact_type) :: con
    type(ellip_type) :: ellip

    res = !whatever this should do
  end function f
end module condact_module


!> A program using the condact functionality.
program test_condact
  use ellip_module
  use condact_module

  implicit none

  type(condact_type) :: mycon
  type(ellip_type) :: myellip
  integer :: i,j
  real :: res

  call condact(i,j, mycon, myellip, res)
end program test_condact

This is just a rough sketch, but I got the impression this is what you are looking for.