#1. [1, 2, 3]*3 -> [1, 2, 3, 1, 2, 3, 1, 2, 3]
#2. 3 in [1, 2, 3, 4]-> True 和 [3] in [1, 2, 3, 4]->False
#3. 列表与整数的乘法生成包含10个数字5的列表, 可以写为: [5]*10
#5. list(range(1, 10, 3))的值->[1, 4, 7]
#6. list(range(10, 1, -3))-> [10, 7, 4]
#7. list(range(5))的值->[0, 1, 2, 3, 4]
#8. 列表的()方法删除首次出现的指定元素, 如果不存在指定删除的元素则抛出异常
#9. 列表[1, 2, -1, 4]的排序后的逆序-> sorted([1, 2, -1, 4], reverse=True)
字符串中可以使用的符号总结
+, -, in, not in, is, not is, []
在列表中支持的符号有
+, *, in, not in,
列表中可以存放: 字符串类型, 浮点型, 列表, 元组, 字典, 对象等
demo01 集合
l1 = [1, 2, 3]
l2 = [5, 6, 7]
l3 = l1 + l2
print(l3)
l4 = [5, 8]
print(l4 * 3)
l5 = [1, 2, 3, 4]
result = 3 in l5
print(result)
result = [3] in [1, 2, 3, 4, [3]]
print(result)
print("1----------")
l6 = [[1, 2], [1, 2, 3] ,[4, 5]]
print(len(l6))
print(l6[1][2], type(l6[1]))
print(list(range(1, 10, 3)))
print(list("a, b, c"))
#print(list(10))--> int object is not iterable
# 可迭代的是列表, 字符串, range(5)这种, 在for .. in..中就可迭代
print("2---------")
l7 = [1, 2, 3]
l7.insert(1, 4)
print(l7)
l7.append(10)
print(l7)
l7.extend([1, 2, 3])
print(l7)
print("3-----------")
s1 = "123"
print(s1*2)
print(s1+str("456"))
s1 = "this is a test"
print(s1.count("s"))
print(s1[s1.find('test'): s1.find('test')+4])
print(s1.replace('test', 'hhhh'))
print("4-------------")
#大小写互相转换
a = 'aaFKNdyuK'
s = ''
for i in a:
if i.isupper():
s+=i.lower()
elif i.islower():
s+=i.upper()
else:
s+=i
print("a:", s)
print("5-------------join")
x='abc'
y='def'
z=['d', 'e', 'f']
print(x.join(y))
print(x.join(z))
print("6-------------字节流")
print("中文".encode('utf-8'))
print("7-------------去除空格")
print(" abc ".strip())
# 运行结果
[1, 2, 3, 5, 6, 7]
[5, 8, 5, 8, 5, 8]
True
True
1----------
3
3 <class 'list'>
[1, 4, 7]
['a', ',', ' ', 'b', ',', ' ', 'c']
2---------
[1, 4, 2, 3]
[1, 4, 2, 3, 10]
[1, 4, 2, 3, 10, 1, 2, 3]
3-----------
123123
123456
3
test
this is a hhhh
4-------------
a: AAfknDYUk
5-------------join
dabceabcf
dabceabcf
6-------------字节流
b'\xe4\xb8\xad\xe6\x96\x87'
7-------------去除空格
abc
demo02 集合
列表函数
append(''), extend(''), insert('')
del, remove, pop, clear
name_list = ['lucy', 'tom', 'mark', 'jenny', 'jack']
name_list.append('mark')#不返回结果
print(name_list)
name_list.remove('mark')#返回结果, 如果元素没有则报异常
print(name_list)
result = name_list.pop(2)#没有index默认最后一个
print(result)
print(name_list)
# result = name_list.clear() #不返回结果
# print(result)
print(name_list[::-1])
print(name_list)
name_list.reverse()
print(name_list)
num_list = [3, 4, 2, 1, 3]
print(sorted(num_list)) #不改变原数组
print(num_list)
num_list.sort(reverse=True)
print(num_list)
print(num_list.count(3))# 不存在抛异常
['lucy', 'tom', 'mark', 'jenny', 'jack', 'mark']
['lucy', 'tom', 'jenny', 'jack', 'mark']
jenny
['lucy', 'tom', 'jack', 'mark']
['mark', 'jack', 'tom', 'lucy']
['lucy', 'tom', 'jack', 'mark']
['mark', 'jack', 'tom', 'lucy']
[1, 2, 3, 3, 4]
[3, 4, 2, 1, 3]
[4, 3, 3, 2, 1]
2