[f2py] A mostly working example

[James Amundson]

On Fri, 2002-03-22 at 13:00, Pearu Peterson wrote:
> > 
> > Why does the argument to foo only get modified if it is a Numeric array?
> > Is that the desired behavior?
> 
> Yes, and it is the only possible behaviour because Python integers are
> immutable and they cannot modified in situ. Numeric array is mutable and
> it can be modified in situ.

Ah, I see. That wasn't clear to me at all. Thanks.

> However note that using intent(inout) variables are depreciated exactly
> due to this issue. Using intent(in,out) is recommended for
> variables that are both input and output.
> 
> Regards,
> 	Pearu
> 


But intent(in,out) doesn't work! Here's the new foo.f:

! Fortran file foo.f:
      subroutine foo(a)
      integer a
cf2py  intent(in,out) a
      a = a + 5
      end

Here's what happens when I use it:

|abacus>python
Python 2.1.1 (#1, Feb 18 2002, 14:18:11) 
[GCC 2.96 20000731 (Red Hat Linux 7.1 2.96-85)] on linux2
Type "copyright", "credits" or "license" for more information.
>>> import foobar
>>> from Numeric import *
>>> a = array(1)
>>> print a,foobar.foo(a),a
1 6 1
>>> print foobar.__doc__
This module 'foobar' is auto-generated with f2py
(version:2.13.175-1233).
Functions:
  a = foo(a)
  bar = bar(a,b)
.
>>> 

I only get the correct behavior for foo if I use intent(inout).

Thanks,
Jim