python列表操作

fruits = [‘apple‘, ‘orange‘, ‘banana‘, ‘pear‘, ‘watermelon‘]
print (fruits)

# result 

[‘apple‘, ‘orange‘, ‘banana‘, ‘pear‘, ‘watermelon‘]

1 # 列表中元素以0开始，若显示orange，则：
2 print (fruits[1])
# -1为列表的最后一个元素
print(fruits[-1])
# result
watermelon

fruits[1] = peach
print (fruits)
# result

[‘apple‘, ‘peach‘, ‘banana‘, ‘pear‘, ‘watermelon‘]

fruits.append(‘peach‘)
print(fruits)
# result
[apple, banana, pear, watermelon, peach]

fruits = []
fruits.append(‘apple‘)
fruits.append(‘banana‘)
fruits.append(‘pear‘)
fruits.append(‘watermelon‘)
print(fruits)

# result
[‘apple‘, ‘banana‘, ‘pear‘, ‘watermelon‘]

fruits.insert(1, peach)
print(fruits)

# result
[‘apple‘, ‘peach‘, ‘banana‘, ‘pear‘, ‘watermelon‘]

# del
del fruits[1]
print (fruits)
# result
[‘apple‘, ‘pear‘, ‘watermelon‘]

# pop()
apple = fruits.pop(0)
print (apple)
print (fruits)
# result
apple
[‘banana‘, ‘pear‘, ‘‘watermelon‘]

# remove()
fruits.remove(‘pear‘)
print(fruits)
# result
[‘apple‘, ‘banana‘, ‘watermelon‘]

# 永久排序
fruits.sort()
print (fruits)
# result
[‘apple‘, ‘banana‘, ‘pear‘, ‘watermelon‘]

# 倒序
fruits.sort(reverse=True)
print(fruits)
[‘watermelon‘, ‘pear‘, ‘banana‘, ‘apple‘]

# 临时排序
print(fruits)
print(sorted(fruits))
print(fruits)
# result 假设原fruits为[ ‘banana‘, ‘apple‘, ‘pear‘, ‘watermelon‘]
[ ‘banana‘, ‘apple‘, ‘pear‘, ‘watermelon‘]
[‘apple‘, ‘banana‘, ‘pear‘, ‘watermelon‘]
[ ‘banana‘, ‘apple‘, ‘pear‘, ‘watermelon‘]

fruits.reverse()
print(fruits)
# result
[‘watermelon‘, ‘pear‘, ‘banana‘, ‘apple‘]

print(len(fruits))
# result
4

for fruit in fruits:
    print(fruit)
# result
apple
banana
peer
watermelon

for value in range(1, 5):
    print (value)
# result 不包含末尾值
1
2
3
4

# 使用range创建数字列表
values = list(range(1, 6))
print (values)
# result
[1, 2, 3, 4, 5]

# 打印偶数
values = list(range(2, 11, 2))
print (values)
# result
[2, 4, 6, 8, 10]

# 数字统计计算
values = [1, 2, 3, 4, 5, 6, 7, 8, 9]
print(min(values))
print(max(values))
print(sum(value))

print(fruits[0:3])
# result 左闭右开 
[‘apple‘, ‘banana‘, ‘pear‘]

print(fruits[:3])
# result 左侧无起始值，则默认从开头位置取，若右侧无终止值，则一直取到list的末尾
[‘apple‘, ‘banana‘, ‘pear‘]

for fruit in fruits[0:3]
    print (fruit)
# result
[‘apple‘, ‘banana‘, ‘pear‘]

my_fruits = fruits[:]
print (my_fruits)
# result
[‘apple‘, ‘banana‘, ‘pear‘, ‘watermelon‘]