1.列表操作
1.赋值
>>>ll = ['2', 'hello', 8.9, ['hahhah', 2]]
>>> list_from_other = list('Hello Wrold!')
>>> list_from_other
['H', 'e', 'l', 'l', 'o', ' ', 'W', 'r', 'o', 'l', 'd', '!']
2.访问
>>> ll[0]
'2'
>>> ll[3]
['hahhah', 2]
>>> ll[3][0]
'hahhah'
>>> ll[-3:-1]
['hello', 8.9]
3.更新
>>> ll[0]=1234567890
>>> ll
[1234567890, 'hello', 8.9, ['hahhah', 2]]
>>> ll.append('This is a test!')
>>> ll
[1234567890, 'hello', 8.9, ['hahhah', 2], 'This is a test!']
>>> l = ['string', 's', 56]
>>> ll.extend(l)
>>> ll
[1234567890, 'hello', 8.9, ['hahhah', 2], 'This is a test!', 'string', 's', 56]
4.删除
>>> del ll[1]
>>> ll
[1234567890, 8.9, ['hahhah', 2], 'This is a test!', 'string', 's', 56]
>>> ll.remove('This is a test!')
>>> ll
[1234567890, 8.9, ['hahhah', 2], 'string', 's', 56]
>>> ll.pop(2)
['hahhah', 2]
>>> ll
[1234567890, 8.9, 'string', 's', 56]
>>> ll.pop()
56
2.序列类型可用的内建函数
>>> alist = [100, 3, 0, 34, 98, 33, 0.3, 54, 23]
1.迭代
>>> for item in alist: #遍历元素
print item
100
3
0
34
98
33
0.3
54
>>> for i in range(len(alist)): #对每个元素进行操作
alist[i] * 2
200
6
0
68
196
66
0.6
108
>>> for index, value in enumerate(alist): #同时返回index和list中的元素
print index, value
0 100
1 3
2 0
3 34
4 98
5 33
6 0.3
7 54
8 23
>>> for i, j in zip(ll, l): #zip()参数可以是dict或tuple，同时输出多个，以最短的为主
print i, j
1234567890 string
8.9 s
string 56
2.len()返回List长度
>>> print len(alist)
9
3.返回List中最大的元素
>>> max(alist)
100
4.返回List中最小的元素
>>> min(alist)
0
5.返回List中元素的和，只有List全部是数字才可以
>>> sum(alist)
345.3
6.sorted()方法返回排序号的序列，有字母时按照ASCⅡ码排序
>>> print sorted(alist)
[0, 0.3, 3, 23, 33, 34, 54, 98, 100]
7.reversed()方法不返回序列，返回一个迭代器
>>> print reversed(alist)
<listreverseiterator object at 0x0000000002053B38>
>>> alist
[100, 3, 0, 34, 98, 33, 0.3, 54, 23]
3.序列操作符
>>> alist = [100, 3, 0, 34, 98, 33, 0.3, 54, 23]
1.成员判断符，'in'或者'not in '
>>> 100 in alist
True
>>> 2 in alist
False
>>> 0 not in alist
False
2.切片'[::]'或者'[:]' slice[n:m]开始的位置包括n，结束在m之前，类似左开右闭区间 [n,m)
>>> alist[::2]
[100, 0, 98, 0.3, 23]
>>> alist[2:5:2]
[0, 98]
>>> alist[::-1]
[23, 54, 0.3, 33, 98, 34, 0, 3, 100]
3.重复操作符'*'
>>> ll = ['2', 'hello', 8.9, ['hahhah', 2]]
>>> list1 = ll * 2
>>> list1
['2', 'hello', 8.9, ['hahhah', 2], '2', 'hello', 8.9, ['hahhah', 2]]
4.连接操作符'+'
>>> list2 = alist + ll
>>> list2
[100, 3, 0, 34, 98, 33, 0.3, 54, 23, '2', 'hello', 8.9, ['hahhah', 2]]
4.列表类型内建函数
list.append(obj)
list.extend(seq)
list.remove(obj)
list.pop([index=-1])
list.count(obj)返回一个obj在List中出现的次数
>>> test_list
[100, 3, 0, 34, 98, 33, 0.3, 54, 23, 3, 1234567890, 8.9, 'string', 's']
>>> test_list.count(3)
2
list.index(obj, i=0, j=len(list)) 在i<=k<j之间返回list[k]==obj的k值
>>> test_list.index(1234567890)
10
>>> test_list.index(3, 2, len(test_list)) #查找第二个3
9
list.sort()与list.reverse()无返回值
>>> test_list.sort()
>>> test_list
[0, 0.3, 3, 3, 8.9, 23, 33, 34, 54, 98, 100, 1234567890, 's', 'string']
>>> test_list.reverse()
>>> test_list
['string', 's', 1234567890, 100, 98, 54, 34, 33, 23, 8.9, 3, 3, 0.3, 0]
list.insert(index, value)插入元素
>>> test_list.insert(2, 'import this')
>>> test_list
['string', 's', 'import this', 1234567890, 100, 98, 54, 34, 33, 23, 8.9, 3, 3, 0.3, 0]
5.列表解析
列表解析的一般语法：[元素或者元素的操作 迭代（for） 条件（if）]
>>> new_list = [x ** 2 for x in range(0, 10) if x % 2 == 0]
>>> new_list
[0, 4, 16, 36, 64]
6.tuple
tuple可以看做不能改变的list，一旦被定义，不可改变
tuple的创建和访问与list一样，但是tuple不可更新，更新意味着创建新的tuple
tuple不能删除一个元素，只能del atuple全部删除
所有多对象的、逗号分隔的、没有明确用符号定义的，这些集合的默认类型都是tuple
所有返回的多对象的都是元组类型
7.用列表构建其他数据类型
- stack：先入后出
#!/usr/bin/env python
#-*- coding:utf-8 -*-
stack = [] #建立存储的stack
#进栈
def pushit():
stack.append(raw_input("Please Enter your String : ").strip())
#出栈
def popit():
if len(stack) == 0:
print "Connot pop from an Empty Stack!"
else:
print "Romove [", `stack.pop()`,"] successful!"
#观察栈
def viewstack():
print stack
CMDs = {'u': pushit, 'o': popit, 'v': viewstack}
#菜单
def showmenu():
pr = """
p(U)sh
P(O)p
(V)iew
(Q)uit
Enter choice: """
while True: #执行命令
while True: #接受输入
try:
choice = raw_input(pr).strip()[0].lower()
except (EOFError, KeyboardInterrupt, IndexError):
choice = 'q'
print '\nYou picked: [%s]' % (choice)
if choice not in 'uovq':
print 'Invalid option, try again'
else:
break
if choice == 'q':
break
CMDs[choice]()
if __name__ == '__main__':
showmenu()
- 队列：先进先出
#!/usr/bin/env python
#-*- coding:utf-8 -*-
queue = []
# 进队列
def enQ():
queue.append(raw_input("Please Enter your String : ").strip())
# 出队列
def delQ():
if len(queue) == 0:
print "Connot pop from an Empty Queue!"
else:
print "Romove [", `queue.pop(0)`, "] successful!" #pop()函数默认为index = -1
# 观察队列
def viewqueue():
print queue
CMDs = {'e': enQ, 'd': delQ, 'v': viewqueue}
# 菜单
def showmenu():
pr = """
(E)nterqueue
(D)delqueue
(V)iew
(Q)uit
Enter choice: """
while True: # 执行命令
while True: # 接收输入
try:
choice = raw_input(pr).strip()[0].lower() # 确保接收输入的第一个非空格字符的小写字母
except (EOFError, KeyboardInterrupt, IndexError):
choice = 'q'
print '\nYou picked: [%s]' % (choice)
if choice not in 'devq':
print 'Invalid option, try again'
else:
break
if choice == 'q':
break
CMDs[choice]()
if __name__ == '__main__':
showmenu()
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