学习笔记：python列表2

python学习

列表的进一步运用

1.减少元素

（1）del

place = ['lasa', 'chengdu', 'litang', 'xian', 'lundon']
del place[0]

#输出

['chengdu', 'litang', 'xian', 'lundon']

（2）pop（）

place = ['lasa', 'chengdu', 'litang', 'xian', 'lundon']
print(place.pop(0))

#输出为
['chengdu', 'litang', 'xian', 'lundon']

区别：pop（）在去掉元素后还能够继续使用他

2.增加元素

（1）append（）

name = ['yebenhao','luyuhao','liuyufan']
name.append('hewenhao')
print(name)

（2）insert（）

name = ['yebenhao','luyuhao','liuyufan']
name.insert(0,'chenyifan')
print(name)

3.sort,sorted,reverse的用法

place = ['lasa', 'chengdu', 'litang', 'xian', 'lundon']
print(sorted(place))
print(place)
print(sorted(place,reverse=True))
print(place)
print(place.reverse())
print(place)
print(place.reverse())
print(place)
print(place.sort())
print(place)
print(place.sort(reverse=True))

#输出为

4.列表的循环

names = ['yebenhao','luyuhao','liuyufan']
for name in names:
    print(f'{name.title()},is dog.')
print("They are my friends.")

#输出为

5.列表元素值最大和最小，求和

numbers = list(range(1,100000))
print(sum(numbers))
print(max(numbers))
print(min(numbers))

6.列表和range的用法

numbers = list(range(3,30,3))
for number in numbers:
    print(number)

7.复制列表

a = [0,1,2,3,4]
b = a[:]
print(a)
print(b)

只看以上和

a =[0,1,2,3,4]
b = a
print(a)
print(b)

输出之后没有差别，但是如果输出以下

a = [0,1,2,3,4]
b = a[:]
a.append(4)
b.insert(0,4)
print(a)
print(b)
#输出为
[0, 1, 2, 3, 4, 4]
[4, 0, 1, 2, 3, 4]

如果仍用第一种写法

a = [0,1,2,3,4]
b = a
a.append(4)
b.insert(0,4)
print(a)
print(b) 
#输出为