Files: sf.f90, stream_function_wrapper.py, setup.py, __init__.py

In order to distribute this to others we'd need to organize the thing a bit better.

First of all we'll assume everything is going to be put in a directory called "sf" after the name of the package we're creating

In this directory we will separate the fortran code from the python code

we will create 2 sub-directory: Src for the fortran and Lib for the python

In Src we will put the file sf.f90 and Lib we will put the file stream_function_wrapper.py

Now that this is done we need to create a "setup" file for the python packaging suite tool, it is called "setup.py"

This file uses numpy.distutils.core

You can pretty much go throught it w/o really understanding it, just copy paste,

The basics you need to know are:

files: List of the FORTRAN files needed

extra_link_args : if you need special arguments when building your fortran

libraries: a list of library name that are external and you need to link

library_dirs : a list of additional directories where to look for the libraries

include_dirs: list of places where to look for include files

name/package_dir: ususally the same name (sf), the one in package_dir/packages is the one that matters to you

import sys

# Gather up all the files we need.
files = ['Src/sf.f90',]

## scypy_distutils Script
from numpy.distutils.core import setup, Extension

extra_link_args=[]
if sys.platform=='darwin':
    extra_link_args = ['-bundle','-bundle_loader '+sys.prefix+'/bin/python']
    
## setup the python module
setup(name="sf", # name of the package to import later
      ## Build fortran wrappers, uses f2py
      ## directories to search for libraries defined in setup.cfg
      ext_modules = [Extension('streamfunction',
                               files,
#                              libraries=[],
#                              library_dirs=[],
#   			       include_dirs=['Src'],
                               extra_link_args=extra_link_args,
                               ),
                     ],
      
##      ## Install these to their own directory
     package_dir={'sf':'Lib'},
     packages = ["sf"],
      
     )

Finally in the Lib directory we need to add a file called __init__.py that is executed when importing the package. Basivally this simply expose the function we want to the user

## Figures out which function we expose
from stream_function_wrapper import zm_msf

Now all we need to do is to build and install this package

from the sf directory type:

python setup.py build

Now if you are superuser or have write permission to your python distribution directories you can type

python setup.py install

Usually you won't have write permission, no worries, all you need to do is:

python setup.py install --prefix=/mydir

Now you have one more thing to do before you can use this package:

in the script that will import the package add the following lines:

import sys
sys.path.append("/mydir/lib/python2.5/site-packages")
import sf

If your python is not 2.5, replace this with whatever version your python is.

That's it! Enjoy!