def reverse_with_set_values(d, sort=False): ''' Reverse the dict, with the values of the new dict being sets. Example: reverse_with_set_values({1: 2, 3: 4, 'meow': 2}) == \ {2: {1, 'meow'}, 4: {3}} Instead of a dict you may also input a tuple in which the first item is an iterable and the second item is either a key function or an attribute name. A dict will be constructed from these and used. If you'd like the result dict to be sorted, pass `sort=True`, and you'll get a sorted `OrderedDict`. You can also specify the sorting key function or attribute name as the `sort` argument. ''' ### Pre-processing input: ################################################# # # if hasattr(d, 'items'): # `d` is a dict fixed_dict = d else: # `d` is not a dict assert cute_iter_tools.is_iterable(d) and len(d) == 2 iterable, key_function_or_attribute_name = d assert cute_iter_tools.is_iterable(iterable) key_function = comparison_tools.process_key_function_or_attribute_name( key_function_or_attribute_name ) fixed_dict = {key: key_function(key) for key in iterable} # # ### Finished pre-processing input. ######################################## new_dict = {} for key, value in fixed_dict.items(): if value not in new_dict: new_dict[value] = [] new_dict[value].append(key) # Making into sets: for key, value in new_dict.copy().items(): new_dict[key] = set(value) if sort: from python_toolbox import nifty_collections ordered_dict = nifty_collections.OrderedDict(new_dict) if isinstance(sort, (collections.Callable, str)): key_function = comparison_tools. \ process_key_function_or_attribute_name(sort) else: assert sort is True key_function = None ordered_dict.sort(key_function) return ordered_dict else: return new_dict
def reverse_with_set_values(d, sort=False): ''' Reverse the dict, with the values of the new dict being sets. Example: reverse_with_set_values({1: 2, 3: 4, 'meow': 2}) == \ {2: {1, 'meow'}, 4: {3}} Instead of a dict you may also input a tuple in which the first item is an iterable and the second item is either a key function or an attribute name. A dict will be constructed from these and used. If you'd like the result dict to be sorted, pass `sort=True`, and you'll get a sorted `OrderedDict`. You can also specify the sorting key function or attribute name as the `sort` argument. ''' ### Pre-processing input: ################################################# # # if hasattr(d, 'items'): # `d` is a dict fixed_dict = d else: # `d` is not a dict assert cute_iter_tools.is_iterable(d) and len(d) == 2 iterable, key_function_or_attribute_name = d assert cute_iter_tools.is_iterable(iterable) key_function = comparison_tools.process_key_function_or_attribute_name( key_function_or_attribute_name ) fixed_dict = {key: key_function(key) for key in iterable} # # ### Finished pre-processing input. ######################################## new_dict = {} for key, value in fixed_dict.iteritems(): if value not in new_dict: new_dict[value] = [] new_dict[value].append(key) # Making into sets: for key, value in new_dict.copy().iteritems(): new_dict[key] = set(value) if sort: from python_toolbox import nifty_collections ordered_dict = nifty_collections.OrderedDict(new_dict) if isinstance(sort, (collections.Callable, basestring)): key_function = comparison_tools. \ process_key_function_or_attribute_name(sort) else: assert sort is True key_function = None ordered_dict.sort(key_function) return ordered_dict else: return new_dict
def sort(self, key=None, reverse=False): """ Sort the items according to their keys, changing the order in-place. The optional `key` argument, (not to be confused with the dictionary keys,) will be passed to the `sorted` function as a key function. """ key_function = comparison_tools.process_key_function_or_attribute_name(key) sorted_keys = sorted(self.keys(), key=key_function, reverse=reverse) for key_ in sorted_keys[1:]: self.move_to_end(key_)
def sort(self, key=None, reverse=False): ''' Sort the items according to their keys, changing the order in-place. The optional `key` argument, (not to be confused with the dictionary keys,) will be passed to the `sorted` function as a key function. ''' key_function = \ comparison_tools.process_key_function_or_attribute_name(key) sorted_keys = sorted(self.keys(), key=key_function, reverse=reverse) for key_ in sorted_keys[1:]: self.move_to_end(key_)
def sort(self, key=None, reverse=False): ''' Sort the items according to their keys, changing the order in-place. The optional `key` argument will be passed to the `sorted` function as a key function. ''' # Inefficient implementation until someone cares. key_function = \ comparison_tools.process_key_function_or_attribute_name(key) sorted_members = sorted(tuple(self), key=key_function, reverse=reverse) self.clear() self |= sorted_members
def get_equivalence_classes(iterable, key=None, container=set, *, use_ordered_dict=False, sort_ordered_dict=False): ''' Divide items in `iterable` to equivalence classes, using the key function. Each item will be put in a set with all other items that had the same result when put through the `key` function. Example: >>> get_equivalence_classes(range(10), lambda x: x % 3) {0: {0, 9, 3, 6}, 1: {1, 4, 7}, 2: {8, 2, 5}} Returns a `dict` with keys being the results of the function, and the values being the sets of items with those values. Alternate usages: Instead of a key function you may pass in an attribute name as a string, and that attribute will be taken from each item as the key. Instead of an iterable and a key function you may pass in a `dict` (or similar mapping) into `iterable`, without specifying a `key`, and the value of each item in the `dict` will be used as the key. Example: >>> get_equivalence_classes({1: 2, 3: 4, 'meow': 2}) {2: {1, 'meow'}, 4: {3}} If you'd like the result to be in an `OrderedDict`, specify `use_ordered_dict=True`, and the items will be ordered according to insertion order. If you'd like that `OrderedDict` to be sorted, pass in `sort_ordered_dict=True`. (It automatically implies `use_ordered_dict=True`.) You can also pass in a sorting key function or attribute name as the `sort_ordered_dict` argument. ''' from python_toolbox import comparison_tools ### Pre-processing input: ################################################# # # if key is None: if isinstance(iterable, collections.abc.Mapping): d = iterable else: try: d = dict(iterable) except ValueError: raise Exception( "You can't put in a non-dict without also supplying a " "`key` function. We need to know which key to use." ) else: # key is not None assert cute_iter_tools.is_iterable(iterable) key_function = comparison_tools.process_key_function_or_attribute_name( key ) d = {key: key_function(key) for key in iterable} # # ### Finished pre-processing input. ######################################## if use_ordered_dict or sort_ordered_dict: from python_toolbox import nifty_collections new_dict = nifty_collections.OrderedDict() else: new_dict = {} for key, value in d.items(): new_dict.setdefault(value, []).append(key) # Making into desired container: for key, value in new_dict.copy().items(): new_dict[key] = container(value) if sort_ordered_dict: if isinstance(sort_ordered_dict, (collections.abc.Callable, str)): key_function = comparison_tools. \ process_key_function_or_attribute_name(sort_ordered_dict) new_dict.sort(key_function) elif sort_ordered_dict is True: new_dict.sort() return new_dict else: return new_dict
def get_equivalence_classes(iterable, key=None, container=set, use_ordered_dict=False, sort_ordered_dict=False): ''' Divide items in `iterable` to equivalence classes, using the key function. Each item will be put in a set with all other items that had the same result when put through the `key` function. Example: >>> get_equivalence_classes(range(10), lambda x: x % 3) {0: {0, 9, 3, 6}, 1: {1, 4, 7}, 2: {8, 2, 5}} Returns a `dict` with keys being the results of the function, and the values being the sets of items with those values. Alternate usages: Instead of a key function you may pass in an attribute name as a string, and that attribute will be taken from each item as the key. Instead of an iterable and a key function you may pass in a `dict` (or similar mapping) into `iterable`, without specifying a `key`, and the value of each item in the `dict` will be used as the key. Example: >>> get_equivalence_classes({1: 2, 3: 4, 'meow': 2}) {2: {1, 'meow'}, 4: {3}} If you'd like the result to be in an `OrderedDict`, specify `use_ordered_dict=True`, and the items will be ordered according to insertion order. If you'd like that `OrderedDict` to be sorted, pass in `sort_ordered_dict=True`. (It automatically implies `use_ordered_dict=True`.) You can also pass in a sorting key function or attribute name as the `sort_ordered_dict` argument. ''' from python_toolbox import comparison_tools ### Pre-processing input: ################################################# # # if key is None: if isinstance(iterable, collections.Mapping): d = iterable else: try: d = dict(iterable) except ValueError: raise Exception( "You can't put in a non-dict without also supplying a " "`key` function. We need to know which key to use." ) else: # key is not None assert cute_iter_tools.is_iterable(iterable) key_function = comparison_tools.process_key_function_or_attribute_name( key ) d = dict((key, key_function(key)) for key in iterable) # # ### Finished pre-processing input. ######################################## if use_ordered_dict or sort_ordered_dict: from python_toolbox import nifty_collections new_dict = nifty_collections.OrderedDict() else: new_dict = {} for key, value in d.items(): new_dict.setdefault(value, []).append(key) # Making into desired container: for key, value in new_dict.copy().items(): new_dict[key] = container(value) if sort_ordered_dict: if isinstance(sort_ordered_dict, (collections.Callable, str)): key_function = comparison_tools. \ process_key_function_or_attribute_name(sort_ordered_dict) new_dict.sort(key_function) elif sort_ordered_dict is True: new_dict.sort() return new_dict else: return new_dict