Source code for pml.utils.collection_utils
# Copyright (C) 2012 David Rusk
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"""
Utilities for working with collections.
@author: drusk
"""
import collections
import operator
[docs]def get_key_with_highest_value(dictionary):
"""
Retrieves the key with the highest value from a dictionary.
Args:
dictionary: dict
The dictionary whose keys and values are being examined.
Returns:
key:
The key with the highest value. Returns None if the dictionary
is empty.
"""
if len(dictionary) == 0:
return None
return max(dictionary.iteritems(), key=operator.itemgetter(1))[0]
[docs]def are_all_equal(iterable):
"""
Checks if all elements of a collection are equal.
Args:
iterable: iterator
A collection of values such as a list.
Returns:
equal: boolean
True if all elements of iterable are equal. Will also return true if
iterable is empty.
"""
return len(set(iterable)) <= 1
[docs]def get_most_common(iterable):
"""
Finds the item which occurs most often in a collection of values.
Args:
iterable: iterator
The items which will be searched to find the most common.
Returns:
most_common:
The most common item in the collection. Ties are broken arbitrarily.
"""
counts = collections.defaultdict(int)
for item in iterable:
counts[item] += 1
return get_key_with_highest_value(counts)