Python reduce Examples

Example #1

 def enqueue(self, el):
     """Returns new queue object with given element is added onto the end"""
     # check if we need to rebalance to prevent spikes
     if len(self.left) >= len(self.right):
         return Queue(self.left, self.right.cons(el))
     left = reduce(lambda acc, el: acc.cons(el), self.right, self.left)
     return Queue(left, LinkedList().cons(el))

Example #2

File: list.py Project: dbinthesky/fn.py

 def enqueue(self, el):
     """Returns new queue object with given element is added onto the end"""
     # check if we need to rebalance to prevent spikes
     if len(self.left) >= len(self.right):
         return Queue(self.left, self.right.cons(el))
     left = reduce(lambda acc, el: acc.cons(el), self.right, self.left)
     return Queue(left, LinkedList().cons(el))

Example #3

File: trie.py Project: soasme/fn.py

 def _find_container(self, pos):
     if pos < 0 or pos > self.length:
         raise IndexError()
     if pos >= self._tailoff():
         return self.tail
     bottom = reduce(lambda node, level: node.array[(pos >> level) & 0x01f],
                     range(self.shift, 0, -5), self.root)
     return bottom.array

Example #4

File: tests.py Project: Gizmo707/fn.py

 def test_cons_operation(self):
     v = Vector()
     self.assertEqual(0, len(v))
     v1 = v.cons(10)
     self.assertEqual(1, len(v1))
     self.assertEqual(0, len(v)) # previous value didn't change
     up = reduce(lambda acc, el: acc.cons(el), range(513), Vector())
     self.assertEqual(513, len(up))

Example #5

File: trie.py Project: cad106uk/fn.py

 def _find_container(self, pos):
     if pos < 0 or pos > self.length:
         raise IndexError()
     if pos >= self._tailoff():
         return self.tail
     bottom = reduce(lambda node, level: node.array[(pos >> level) & 0x01f],
                     range(self.shift, 0, -5), self.root)
     return bottom.array

Example #6

File: tests.py Project: pawroman/fn.py

 def test_cons_operation(self):
     v = Vector()
     self.assertEqual(0, len(v))
     v1 = v.cons(10)
     self.assertEqual(1, len(v1))
     self.assertEqual(0, len(v))  # previous value didn't change
     up = reduce(lambda acc, el: acc.cons(el), range(513), Vector())
     self.assertEqual(513, len(up))

Example #7

File: trie.py Project: cad106uk/fn.py

 def __iter__(self):
     s = reduce(
         lambda acc, el: acc << (
             el if isinstance(el, self.__class__) else [el]
         ),
         takewhile(lambda el: el is not None, self.array),
         Stream()
     )
     return iter(s)

Example #8

File: util.py Project: HackDaemon/Passwd-Zuma

def unpackStrList(lists):
    def reduceStr(total, s):
        if isinstance(s, list):
            return total + s
        else:
            total.append(s)
            return total

    return list(reduce(reduceStr, lists, []))

Example #9

File: list.py Project: dbinthesky/fn.py

    def dequeue(self):
        """Return pair of values: the item from the front of the queue and
        the new queue object without poped element.
        """
        if not self: raise ValueError("Queue is empty")
        # if there is at least one element on the left, we can return it
        if self.left:
            return self.left.head, Queue(self.left.tail, self.right)

        # in other case we need to copy right to left before
        d = reduce(lambda acc, el: acc.cons(el), self.right, LinkedList())
        return d.head, Queue(d.tail, LinkedList())

Example #10

    def dequeue(self):
        """Return pair of values: the item from the front of the queue and
        the new queue object without poped element.
        """
        if not self: raise ValueError("Queue is empty")
        # if there is at least one element on the left, we can return it
        if self.left:
            return self.left.head, Queue(self.left.tail, self.right)

        # in other case we need to copy right to left before
        d = reduce(lambda acc, el: acc.cons(el), self.right, LinkedList())
        return d.head, Queue(d.tail, LinkedList())

Example #11

File: tests.py Project: zhenyu-captain/fn.py

 def test_assoc_get_operations(self):
     v = Vector()
     v1 = v.assoc(0, 10)
     v2 = v1.assoc(1, 20)
     v3 = v2.assoc(2, 30)
     self.assertEqual(10, v3.get(0))
     self.assertEqual(20, v3.get(1))
     self.assertEqual(30, v3.get(2))
     # check persistence
     v4 = v2.assoc(2, 50)
     self.assertEqual(30, v3.get(2))
     self.assertEqual(50, v4.get(2))
     # long vector
     up = reduce(lambda acc, el: acc.assoc(el, el*2), range(1500), Vector())
     self.assertEqual(2800, up.get(1400))
     self.assertEqual(2998, up.get(1499))

Example #12

File: tests.py Project: Gizmo707/fn.py

 def test_assoc_get_operations(self):
     v = Vector()
     v1 = v.assoc(0, 10)
     v2 = v1.assoc(1, 20)
     v3 = v2.assoc(2, 30)
     self.assertEqual(10, v3.get(0))
     self.assertEqual(20, v3.get(1))
     self.assertEqual(30, v3.get(2))
     # check persistence
     v4 = v2.assoc(2, 50)
     self.assertEqual(30, v3.get(2))
     self.assertEqual(50, v4.get(2))
     # long vector
     up = reduce(lambda acc, el: acc.assoc(el, el*2), range(1500), Vector())
     self.assertEqual(2800, up.get(1400))
     self.assertEqual(2998, up.get(1499))

Example #13

File: tests.py Project: pawroman/fn.py

 def test_vector_iterator(self):
     v = reduce(lambda acc, el: acc.assoc(el, el + 1), range(1500),
                Vector())
     self.assertEqual(list(range(1, 1501)), list(v))
     self.assertEqual(1125750, sum(v))

Example #14

File: test_underscore.py Project: cad106uk/fn.py

 def test_repr_parse_str(self):
     self.assertEqual('=> ' + _, eval(repr('=> ' + _)))
     self.assertEqual(
         reduce(lambda f, n: f.format(n), ('({0} & _)',) * 11).format('_'),
         repr(reduce(_ & _, (_,) * 12)),
     )

Example #15

File: basics.py Project: nexxTM/functional_programming-python

# recursion again
def reduce2(f, xs, start):
    if xs:
        return f(xs[0], reduce2(f, xs[1:], start))
    else:
        return start


def reduce3(f, xs, accumulator):
    if xs:
        return reduce3(f, xs[1:], f(xs[0], accumulator))
    else:
        return accumulator


falsify("reduce vs reduce1", lambda xs, s: reduce(add, xs, s) == reduce1(add, xs, s), [int], int)
falsify("reduce1 vs reduce2", lambda xs, s: reduce1(add, xs, s) == reduce2(add, xs, s), [int], int)
falsify("reduce2 vs reduce3", lambda xs, s: reduce2(add, xs, s) == reduce3(add, xs, s), [int], int)


# higher order cont
def doubles(xs):
    return map(lambda x: x * 2, xs)


falsify("doubles", lambda xs: not xs or nth(doubles(xs), 0) == xs[0] * 2, [int])


# partial application
def doubles1(xs):
    return map(partial(mul, 2), xs)

Example #16

File: tests.py Project: Gizmo707/fn.py

 def test_index_error(self):
     v = reduce(lambda acc, el: acc.assoc(el, el+2), range(50), Vector())
     self.assertRaises(IndexError, v.get, -1)
     self.assertRaises(IndexError, v.get, 50)
     self.assertRaises(IndexError, v.get, 52)

Example #17

File: tests.py Project: Gizmo707/fn.py

 def test_vector_iterator(self):
     v = reduce(lambda acc, el: acc.assoc(el, el+1), range(1500), Vector())
     self.assertEqual(list(range(1, 1501)), list(v))
     self.assertEqual(1125750, sum(v))

Example #18

File: tests.py Project: Gizmo707/fn.py

 def test_pop_operations(self):
     v = reduce(lambda acc, el: acc.cons(el), range(2000), Vector())
     self.assertEqual(1999, len(v.pop()))
     self.assertEqual(list(range(1999)), list(v.pop()))

Example #19

File: tests.py Project: pawroman/fn.py

 def test_index_error(self):
     v = reduce(lambda acc, el: acc.assoc(el, el + 2), range(50), Vector())
     self.assertRaises(IndexError, v.get, -1)
     self.assertRaises(IndexError, v.get, 50)
     self.assertRaises(IndexError, v.get, 52)

Example #20

File: tests.py Project: pawroman/fn.py

 def test_pop_operations(self):
     v = reduce(lambda acc, el: acc.cons(el), range(2000), Vector())
     self.assertEqual(1999, len(v.pop()))
     self.assertEqual(list(range(1999)), list(v.pop()))

Example #21

File: util.py Project: HackDaemon/Passwd-Zuma

def unpackList(lists):
    return list(reduce((lambda x, y: x + y), lists))

Example #22

File: tests.py Project: tek/fn.py

 def test_repr_parse_str(self):
     self.assertEqual("=> " + _, eval(repr("=> " + _)))
     self.assertEqual(
         reduce(lambda f, n: f.format(n), ("({0} & _)",) * 11).format("_"), repr(reduce(_ & _, (_,) * 12))
     )

Example #23

File: finger.py Project: soasme/fn.py

 def from_iterable(measure, it):
     tree = FingerTree.Empty(measure)
     return reduce(lambda acc, curr: acc.push_front(curr), it, tree)

Example #24

File: basics.py Project: nexxTM/functional_programming-python

def filter4(pred, xs):
    return reduce(lambda ys, y: ys + [y] if pred(y) else ys, xs, [])

Example #25

File: basics.py Project: nexxTM/functional_programming-python

def map4(f, xs):
    return reduce(lambda ys, y: ys + [f(y)], xs, [])

Example #26

File: basics.py Project: nexxTM/functional_programming-python

def fac1(n):
    return reduce(mul, range(1, n + 1), 1)

Example #27

File: trie.py Project: soasme/fn.py

 def __iter__(self):
     s = reduce(
         lambda acc, el: acc <<
         (el if isinstance(el, self.__class__) else [el]),
         takewhile(lambda el: el is not None, self.array), Stream())
     return iter(s)

Example #28

 def test_repr_parse_str(self):
     self.assertEqual('=> ' + _, eval(repr('=> ' + _)))
     self.assertEqual(
         reduce(lambda f, n: f.format(n), ('({0} & _)', ) * 11).format('_'),
         repr(reduce(_ & _, (_, ) * 12)),
     )

Example #29

File: finger.py Project: FunctionalX/FunctionalX.py

 def from_iterable(measure, it):
     tree = FingerTree.Empty(measure)
     return reduce(lambda acc, curr: acc.push_front(curr), it, tree)

Example #30

File: html.py Project: ccfontes-code-tests/ebay-html-categories

def table_rows(row_dicts):
    return reduce(add, map(table_row, row_dicts))