This set of posts was inspired by Smart enumeration of a subset of graphs obtained from a parent graph question.

If this is your first time it might be useful to review the first post of this series.

Advanced Usage

I’ve updated the try/else block of code some to hopefully allow for an easier time of perhaps applying $R$ as a modifier, hint self['buffer'].update(buffer['modifier'](next_sub_graph)), here’s a quick example…

def populate(sub_graph):
    """
    Expects `{'hash': {'key': None}}` structure where `key` needs a population
    """
    key = 'points'
    hash = sub_graph.keys()[0]
    for x in range(randint(2, 5)):
        sub_graph[hash][key].update(
            {
                "point_{0}".format(x): randint(200, 500),
            }
        )

    return sub_graph

buffer['modifier'] = point_populate

Note assigning a modifier may also be done at initialization too.

… so doing the same loop over buffer (once buffer['graph'] has been refilled and buffer['priority']['GE_bound'] reset) should now produce results similar to…

Chunk 0 of ~ 4
    sub_graph_11 -> {
        'points': {
            'point_0': 379,
            'point_1': 478},
        'first_to_compute': 7}

    sub_graph_10 -> {
        'points': {
            'point_0': 433,
            'point_1': 377,
            'point_2': 462},
        'first_to_compute': 8}
    # ...
#...

… the populate function is being called only on those who are within the priority range!

As there maybe some following along with an empty buffer['graph'], here’s how to repopulate and re-set bits within buffer for re-looping…

buffer['modifier'] = populate
buffer['priority']['GE_bound'] = 7

for i in range(0, 21, 1):
    buffer['graph'].update({
        "sub_graph_{0}".format(i): {
            'points': {},
            'first_to_compute': randint(0, 9),
        }
    })

… and re-looping would be much like it was before

counter = 0
c_max = int(len(graph.keys()) / buffer['buffer_size'] + 1)


for chunk in buffer:
    print("Chunk {0} of ~ {1}".format(counter, c_max - 1))

    for key, val in chunk['buffer'].items():
        print("\t{0} -> {1}".format(key, val))

    counter += 1
    if counter > c_max:
        raise Exception("Hunt for bugs!")