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mattmakesmaps/big_pile_of_heap.py

Last active August 29, 2015 14:01
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Use `heapq` To Emit Sorted Dictionaries Based On a Single User-Provided Key.
Raw
big_pile_of_heap.py
#!/usr/bin/env python
# -*- coding: utf-8 -*-
__author__ = 'mkenny'
__date__ = '5/12/14'
"""
OUTPUT
------
Individual Sorted List
[('Andrew', {'age': 33, 'hometown': 'Menlo Park', 'name': 'Andrew'}),
('Doug', {'age': 12, 'hometown': 'London', 'name': 'Doug'}),
('Matt', {'age': 27, 'hometown': 'Oxnard', 'name': 'Matt'})]
Individual Sorted List
[('Jim', {'age': 54, 'hometown': 'Irwindale', 'name': 'Jim'}),
('Stacie', {'age': 98, 'hometown': 'Aberdeen', 'name': 'Stacie'}),
('Vanya', {'age': 7, 'hometown': 'Fremont', 'name': 'Vanya'})]
Individual Sorted List
[('Adam', {'age': 55, 'hometown': 'Santa Paula', 'name': 'Adam'}),
('Pat', {'age': 23, 'hometown': 'Oxnard', 'name': 'Pat'}),
('Pat', {'age': 13, 'hometown': 'Ventura', 'name': 'Pat'})]
Final Sorted Output
[('Adam', {'age': 55, 'hometown': 'Santa Paula', 'name': 'Adam'}),
('Andrew', {'age': 33, 'hometown': 'Menlo Park', 'name': 'Andrew'}),
('Doug', {'age': 12, 'hometown': 'London', 'name': 'Doug'}),
('Jim', {'age': 54, 'hometown': 'Irwindale', 'name': 'Jim'}),
('Matt', {'age': 27, 'hometown': 'Oxnard', 'name': 'Matt'}),
('Pat', {'age': 23, 'hometown': 'Oxnard', 'name': 'Pat'}),
('Pat', {'age': 13, 'hometown': 'Ventura', 'name': 'Pat'}),
('Stacie', {'age': 98, 'hometown': 'Aberdeen', 'name': 'Stacie'}),
('Vanya', {'age': 7, 'hometown': 'Fremont', 'name': 'Vanya'})]
"""
import heapq
import pprint
def make_sorted_list(records, sort_key):
"""
Return a list of two element tuples, sorted by user-provided key of interest.
The first element for each tuple represents the sort_key's value.
The second element represents the entire dictionary (record).
"""
print "Individual Sorted List"
sorted_out = sorted(records, key=lambda k: k[sort_key])
tuple_convert = [(r[sort_key], r) for r in sorted_out]
pprint.pprint(tuple_convert)
return tuple_convert
if __name__ == '__main__':
source = [
{'name': 'Matt', 'hometown': 'Oxnard', 'age': 27},
{'name': 'Andrew', 'hometown': 'Menlo Park', 'age': 33},
{'name': 'Doug', 'hometown': 'London', 'age': 12},
{'name': 'Vanya', 'hometown': 'Fremont', 'age': 7},
{'name': 'Stacie', 'hometown': 'Aberdeen', 'age': 98},
{'name': 'Jim', 'hometown': 'Irwindale', 'age': 54},
{'name': 'Pat', 'hometown': 'Oxnard', 'age': 23},
{'name': 'Pat', 'hometown': 'Ventura', 'age': 13},
{'name': 'Adam', 'hometown': 'Santa Paula', 'age': 55}
]
# From Source, create three sorted lists
elem1 = make_sorted_list(source[0:3], 'name')
elem2 = make_sorted_list(source[3:6], 'name')
elem3 = make_sorted_list(source[6:9], 'name')
heap_iter = heapq.merge(elem1, elem2, elem3)
print "Final Sorted Output"
pprint.pprint([r for r in heap_iter])
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