15個提高效率的Python編程技巧

每次寫Python都會忘記該怎麼寫，最後只能去Stack Overflow查？我也一樣。時間一長，這讓人厭倦。

這15個Python技巧和竅門，可以幫你提高效率。

1.交換值

x, y = 1, 2
print(x, y)
x, y = y, x
print(x, y)

2.字符串列表合併爲一個字符串

sentence_list = ["my", "name", "is", "George"]
sentence_string = " ".join(sentence_list)
print(sentence_string)

3.將字符串拆分爲子字符串列表

sentence_string = "my name is George"
sentence_string.split()
print(sentence_string)

4.通過數字填充初始化列表

[0]*1000 # List of 1000 zeros 
[8.2]*1000 # List of 1000 8.2's

5.字典合併

x = {'a': 1, 'b': 2}
y = {'b': 3, 'c': 4}
z = {**x, **y}

6.反轉字符串

name = "George"
name[::-1]

7.從函數返回多個值

def get_a_string():
  a = "George"
  b = "is"
  c = "cool"
  return a, b, c
sentence = get_a_string()
(a, b, c) = sentence

8.列表解析式

a = [1, 2, 3]
b = [num*2 for num in a] # Create a new list by multiplying each element in a by 2

9.遍歷字典

m = {'a': 1, 'b': 2, 'c': 3, 'd': 4} 
for key, value in m.items():
  print('{0}: {1}'.format(key, value))

10.同時遍歷列表的索引和值

m = ['a', 'b', 'c', 'd']
for index, value in enumerate(m):
  print('{0}: {1}'.format(index, value))

11.初始化空容器

a_list = list()
a_dict = dict()
a_map = map()
a_set = set()

12.刪除字符串兩端的無用字符

name = "  George "
name_2 = "George///"
name.strip() # prints "George"
name_2.strip("/") # prints "George"

13.列表中出現最多的元素

test = [1, 2, 3, 4, 2, 2, 3, 1, 4, 4, 4]
print(max(set(test), key = test.count))

14.檢查對象的內存使用情況

import sys
x = 1
print(sys.getsizeof(x))

15.將dict轉換爲XML

from xml.etree.ElementTree import Element
def dict_to_xml(tag, d):
    '''
    Turn a simple dict of key/value pairs into XML
    '''
    elem = Element(tag)
    for key, val in d.items():
        child = Element(key)
        child.text = str(val)
        elem.append(child)
    return elem

英文原文：

15 Python tips and tricks, so you don’t have to look them up on Stack Overflow