第四章 操作列表

# 遍历整个列表
names = ['athy','irene','gattuso','ash']
for character_name in names:
	print(character_name +"\n")

# for循环-需要让循环的语句缩进
names = ['athy','irene','gattuso','ash']
for character_name in names:
	print(character_name.title() + " is our new character.")
	print(character_name.title() + ",I can't wait to see your next trick!\n")

# for循环结束后执行操作
names = ['athy','irene','gattuso','ash']
for character_name in names:
	print(character_name.title() + " is our new character.\n")
print("Let's be good friends!")

# 创建数值列表
# range()
for value in range(1,5):
	print(value)
print("\n")

# range()创建数字列表
numbers = list(range(1,6))
print(numbers)
numbers = list(range(2,11,2))
print(numbers)
print("\n")

squares = []
for value in range(1,11):
	square = value**2
	squares.append(square)
print(squares)
print("\n")

squares = []
for value in range(1,11):
	squares.append(value**2)
print(squares)
print("\n")

# 对数字列表执行简单的统计计算
digits = [1,2,3,4,5,6,7,8,9,0]
print(min(digits))

digits = [1,2,3,4,5,6,7,8,9,0]
print(max(digits))

digits = [1,2,3,4,5,6,7,8,9,0]
print(sum(digits))
print("\n")

# 列表解析-把for循环和创造新元素的代码合成一行，并且自动附加新元素
squares = [value**2 for value in range(1,11)]
print(squares)
print("\n")

# 切片
names = ['athy','irene','gattuso','ash']
print(names[1:2])

names = ['athy','irene','gattuso','ash']
print(names[:2])

names = ['athy','irene','gattuso','ash']
print(names[1:])

names = ['athy','irene','gattuso','ash']
print(names[-3:])
print("\n")

# 遍历切片
names = ['athy','irene','gattuso','ash']
print("Here are my names:")
for name in names[:2]:
	print(name.title() + "\n")

# 复制列表
my_names = ['athy','irene','gattuso','ash']
other_names = my_names[:]
my_names.append('michael')
other_names.append('arnold')
print("my names:")
print(my_names)
print("other names:")
print(other_names)
print("\n")
# !!要注意复制列表时不可以省略[:]
my_names = ['athy','irene','gattuso','ash']
other_names = my_names
my_names.append('michael')
other_names.append('arnold')
print("my names:")
print(my_names)
print("other names:")
print(other_names)
print("\n")

# 定义元组：不可变的列表
dimensions = (15,19)
print(dimensions[0])
print(dimensions[1])
# “元组中元素”无法修改，即不能赋值

# 修改元组变量
# 可以给“储存元组的”变量赋值
dimensions = (15,19)
print("original:")
for dimension in dimensions:
	print(dimension)
dimensions = (20,19)
print("modified:")
for dimension in dimensions:
	print(dimension)

# 遍历元组中的所有值
dimensions = (15,19)
for dimension in dimensions:
	print(dimension)