Function which returns multiple values

Question

In Fortran, is it possible to define a function which returns multiple values like below?

[a, b] = myfunc(x, y)

Answer 1

That depends... With functions, it is not possible to have two distinct function results. However, you can have an array of length two returned from the function.

  function myfunc(x, y)
    implicit none
    integer, intent(in) :: x,y
    integer             :: myfunc(2)

    myfunc = [ 2*x, 3*y ]
  end function

If you need two return values to two distinct variables, use a subroutine instead:

  subroutine myfunc(x, y, a, b)
    implicit none
    integer, intent(in) :: x,y
    integer, intent(out):: a,b

    a = 2*x
    b = 3*y
  end subroutine