`opendrift.models.openoil.adios.util.many_many`

ManyMany

class for managing a many to many relationship in a pair of dicts

The two mappings are “left” and “right”

The left one is originally populated by the initializer.

After that they are equivalent – when you add something to one the other is updated.

Currently there is no way to remove anything

YOu can access copies of the mappings with:

ManyMany.left and ManyMany.right

They are copies, so that mutating them won’t break the internal data.

Module Contents

initialize a ManyMany structure

class opendrift.models.openoil.adios.util.many_many.ManyMany(initial_data=None)[source]

initialize a ManyMany structure

Parameters:

initial_data –

initial data for the left dict. of the form: {key1: iterable_of_values,

key2: iterable_of_values, … }

all values must be hashable

property left

A copy of the left dict

It’s a copy, so it won’t change the internal ones if mutated

property right

A copy of the right dict

It’s a copy, so it won’t change the internal ones if mutated

static _rebuild(source)[source]: builds a “reversed” dict from a source dict

static _dict_hash(d)[source]

Provide a hash of a dict with a sequence of hashable items as the values

This was to be used to know if an internal dict was changed,: but it turns out that’s not useful (at least not in a robust way)

add_to_left(key, value)[source]

add a new value to the left dict

Parameters:

If the key is already there, the value will be added to the corresponding set

A new key and set will be created if it is not already there.

add_to_right(key, value)[source]

add a new value to the right dict

Parameters:

If the key is already there, the value will be added to the corresponding set

A new key and set will be created if it is not already there.