1. 操作列表，数组列表
#列表操作,构建一个数组
list1=[1,2,3,4,5]
print(list1)
print("The first element is %s" %list1[0])
print("The last element is %s"%list1[-1])
print("The first two elements are%s"%list1[:2])
#数组索引和切片操作与字符串是一样一样的
[1, 2, 3, 4, 5]
The first element is 1
The last element is 5
The first two elements are [1, 2]
2. 向列表中添加元素
list_1=[]
print(list_1)
list_1.append(6) #append,向数组中增加元素
print(list_1)
list_2=['a','b','c']
list_1.extend(list_2) #extend,向数组中增加一个数组
print(list_1)
[]
[6]
[6, 'a', 'b', 'c']
3. 在数组中删除元素
pop和remove是不一样的，remove是移除等于给定值的元素，pop是移除给定位置的元素
list_1=[1,2,3,4,5]
list_1.remove(3) #remove只删除第一个匹配的3
print(list_1)
list_1.pop(3) #pop删除元素的下标为3的字符
print(list_1)
[1, 2, 4, 5]
[1, 2, 4]
4. 遍历数组的每个元素
alist=[i for i in range(30)]
print(alist)
alist=[i for i in range(30) if i%2==0]
print(alist)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29]
[0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28]
alist=[i for i in range(30)]
for number in alist:
if number>3 and number<10:
print(number)
4
5
6
7
8
9
5. 连接数组的每个元素（每个元素必须为字符串)
先把字符串存到列表，再使用join连接，是最合适的连接大量字符串的方式
alist=[1,2,3,4,5]
#print('\t'.join(alist)) This is wrong
alist=[str(i) for i in alist]
print(alist)
print('\t'.join(alist))
print(':'.join(alist))
print(''.join(alist))
blist=['a','b','c','d','e']
print('a'.join(blist))
['1', '2', '3', '4', '5']
1 2 3 4 5
1:2:3:4:5
12345
aabacadae
alist=[1,2,3,4,5]
print(alist)
alist.reverse() #数组反序
print(alist)
alist.sort() #数组元素排序
print(alist)
[1, 2, 3, 4, 5]
[5, 4, 3, 2, 1]
[1, 2, 3, 4, 5]