利用Python进行数据分析

0 魔法命令

!echo "print('Hi')" > test.py

%run test.py

load test.py

1 内置函数

enumerate

test_list = ['apple', 'peach']
mapping = {}
for i, v in enumerate(test_list):
    mapping[v] = i

mapping

== zip==

seq1 = ['apple', 'peach']
seq2 = ['one', 'two']

list(zip(seq1, seq2))

enumerate & zip

for i, (a, b) in enumerate(zip(seq1, seq2)):
	print('{0}: {1}, {2}'.format(i, a, b))

hash

hash('1')

lambda

strings = ['apple', 'peach', 'banana']
strings.sort()
strings

strings.sort(key=lambda x: len(set(list(x))))
strings

currying（柯里化）

def add_numbers(x, y):
    return x + y

add_five = lambda y: add_numbers(5, y)

add_five(1)

from functools import partial
add_one = partial(add_numbers, 1)

add_one(5)