這篇文章主要介紹了給Python初學(xué)者的一些編程技巧,皆是基于基礎(chǔ)的一些編程習(xí)慣建議,需要的朋友可以參考下

交換變量

x = 6y = 5 x, y = y, xprint x>>> 5print y>>> 6

if 語(yǔ)句在行內(nèi)

print "Hello" if True else "World">>> Hello

連接

下面的最后一種方式在綁定兩個(gè)不同類型的對(duì)象時(shí)顯得很co

nfc = ["Packers", "49ers"]afc = ["Ravens", "Patriots"]print nfc + afc>>> ['Packers', '49ers', 'Ravens', 'Patriots'] print str(1) + " world">>> 1 world print `1` + " world">>> 1 world print 1, "world">>> 1 worldprint nfc, 1>>> ['Packers', '49ers'] 1

數(shù)字技巧

#除后向下取整print 5.0//2>>> 2# 2的5次方print 2**5>> 32

注意浮點(diǎn)數(shù)的除法

print .3/.1>>> 2.9999999999999996print .3//.1>>> 2.0

數(shù)值比較

這是我見過諸多語(yǔ)言中很少有的如此棒的簡(jiǎn)便法

x = 2if 3 > x > 1: print x>>> 2if 1 < x > 0: print x>>> 2

同時(shí)迭代兩個(gè)列表

nfc = ["Packers", "49ers"]afc = ["Ravens", "Patriots"]for teama, teamb in zip(nfc, afc): print teama + " vs. " + teamb>>> Packers vs. Ravens>>> 49ers vs. Patriots

帶索引的列表迭代

teams = ["Packers", "49ers", "Ravens", "Patriots"]for index, team in enumerate(teams): print index, team>>> 0 Packers>>> 1 49ers>>> 2 Ravens>>> 3 Patriots

列表推導(dǎo)式

已知一個(gè)列表，我們可以刷選出偶數(shù)列表方法

numbers = [1,2,3,4,5,6]even = []for number in numbers: if number%2 == 0: even.append(number)

轉(zhuǎn)變成如下：

numbers = [1,2,3,4,5,6]even = [number for number in numbers if number%2 == 0]

是不是很牛呢，哈哈。

字典推導(dǎo)

和列表推導(dǎo)類似，字典可以做同樣的工作：

teams = ["Packers", "49ers", "Ravens", "Patriots"]print {key: value for value, key in enumerate(teams)}>>> {'49ers': 1, 'Ravens': 2, 'Patriots': 3, 'Packers': 0}

初始化列表的值

items = [0]*3print items>>> [0,0,0]

列表轉(zhuǎn)換為字符串

teams = ["Packers", "49ers", "Ravens", "Patriots"]print ", ".join(teams)>>> 'Packers, 49ers, Ravens, Patriots'

從字典中獲取元素

我承認(rèn)try/except代碼并不雅致，不過這里有一種簡(jiǎn)單方法，嘗試在字典中查找key，如果沒有找到對(duì)應(yīng)的alue將用第二個(gè)參數(shù)設(shè)為其變量值。

data = {'user': 1, 'name': 'Max', 'three': 4}try: is_admin = data['admin']except KeyError: is_admin = False