Use nopass to simplify the interface for the user-defined function

[arjenmarkus]

The abstract interface func has two arguments, "me" of type "class(root_solver)" and the proper argument of the function. The first serves no purpose for the evaluation of the function and can actually be suppressed:

procedure(func),pointer, nopass :: f => null()  !! user function to find the root of

This way the interface becomes the same as func2 and unifies the usage.

[jacobwilliams]

The reason for it is so in the object-oriented interface you can put data required by the function in the class. Look at the oo example in the repo.

    type,extends(muller_solver_real64) :: my_solver
        integer :: ifunc = 0
        integer :: n = 1
    end type my_solver
    type(my_solver) :: solver

ifunc and n are used in the function.

In my mind, the oo interface is how it should be used, and the functional one is just a wrapper for simple use cases.

[arjenmarkus]

Doesn't this imply that you need a different version of the function for each solver? Op do 19 aug. 2021 om 17:38 schreef Jacob Williams ***@***.***

…

: The reason for it is so in the object-oriented interface you can put data required by the function in the class. Look at the oo example in the repo. type,extends(muller_solver_real64) :: my_solver integer :: ifunc = 0 integer :: n = 1 end type my_solver type(my_solver) :: solver ifunc and n are used in the function. In my mind, the oo interface is how it should be used, and the function one is just a wrapper for simple use cases. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#1 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAN6YR3I6N52W75YLQO5DXDT5UQPJANCNFSM5CIE2INA> . Triage notifications on the go with GitHub Mobile for iOS <https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android <https://play.google.com/store/apps/details?id=com.github.android&utm_campaign=notification-email> .

[jacobwilliams]

No, since the function interface uses root_solver like so:

  function func(me,x)

    class(root_solver),intent(inout) :: me
    real(wp),intent(in) :: x
    real(wp) :: f

    select type (me)
    class is (my_solver)
      f = me%n * sin(x)
      me%ifunc = me%ifunc + 1
    end select 

  end function func

So the same function works for any method. But, you do have to use the annoying select type construct.