Build a dot graph of the Fortran modules in a list of files.

fortran-dot-graph.py

import re

def build_graph(files,exclude=['hdf5','h5lt','mpi']):
    """Build a dot graph of the Fortran modules in a list of files,
    excluding modules named in the list exclude"""

    # Start the graph
    graph = "digraph G {\n"
    deps = {}
    p = re.compile("^(?:module|program) ([a-zA-Z0-9_]*)",
                   re.IGNORECASE+re.MULTILINE)

    for mod in files:
        with open(mod,'r') as f:
            contents = f.read()

        # Get the true module name
        # Careful! It only gets the first module in the file!
        mod_name = re.search(p,contents).group(1)
        # Find all the USE statements and get the module
        deps[mod_name] = re.findall("USE ([a-zA-Z0-9_]*)",contents)

    for k in deps:
        # Remove duplicates and unwanted modules
        deps[k] = list(set(deps[k]) - set(exclude))
        for v in deps[k]:
            # Add the edges to the graph
            edge = k + " -> " + v + ";\n"
            graph = graph + edge

    # Close the graph and return it
    graph = graph + "}"
    return graph