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from operator import add
from functools import partial, reduce

列表解析

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a_list = [item**2 for item in range(5)]
print(a_list)
[0, 1, 4, 9, 16]

字典解析

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a_dict = {"%d^2" % item: item**2 for item in range(5)}
print(a_dict)
{'3^2': 9, '4^2': 16, '2^2': 4, '1^2': 1, '0^2': 0}

生成器

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a_generator = (item**2 for item in range(5))
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print(a_generator)
print(next(a_generator))
print(next(a_generator))
<generator object <genexpr> at 0x103d91200>
0
1

iter函数和next函数

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a_list = ["Jim", "Tom", "Zhang"]
a_list_generator = iter(a_list)
print(next(a_list_generator))
print(next(a_list_generator))
print(type(a_list), type(a_list_generator))
Jim
Tom
<class 'list'> <class 'list_iterator'>

map函数

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print(map(abs, range(-4, 5)))
print(list(map(abs, range(-4, 5))))
print(list(map(lambda x: x**2, range(5))))
print(list(map(lambda x, y: x**y, range(1, 5), range(1, 5))))
<map object at 0x103f2dbe0>
[4, 3, 2, 1, 0, 1, 2, 3, 4]
[0, 1, 4, 9, 16]
[1, 4, 27, 256]

reduce函数

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print(reduce(lambda x, y: x+y, range(10)))
45

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# 求n!
def fn(n):
    return reduce(lambda x, y: x*y,range(1, n+1))
fn(5)
120

filter 函数

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import math
def isPrime(n): # 判定素数
    if n > 2:
        for i in range(2, int(math.sqrt(n)+1)):
            if n % i == 0:
                return False
    elif n ==2:
        return True
    else:
        return False
    return True
list(filter(isPrime, range(100)))
[2,
 3,
 5,
 7,
 11,
 13,
 17,
 19,
 23,
 29,
 31,
 37,
 41,
 43,
 47,
 53,
 59,
 61,
 67,
 71,
 73,
 79,
 83,
 89,
 97]

any和all

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print(all([0, 1, 2]))
False

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print(any([0, 1, 2]))
True

enumerate函数

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for item, index in enumerate(range(1, 6)):
    print("%d: %d" % (index, item))
1: 0
2: 1
3: 2
4: 3
5: 4

zip函数

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for a, b in zip([1, 2, 3], ["a", "b", "c"]):
    print(a, b)
1 a
2 b
3 c

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a_dict = dict(zip([1, 2, 3], ["a", "b", "c"]))
print(a_dict)
{1: 'a', 2: 'b', 3: 'c'}

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print(int("10010", base=2))
int_base_2 = partial(int, base=2)
print(int_base_2("10010"))
int_base_2
18
18





functools.partial(<class 'int'>, base=2)