python快速⼊门第3版电⼦书_python编程：从⼊门到实践第3
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线性代数不会坑的，这两天编辑器t有点抽风，不太好打字，只能先发python了
3.1列表（[ ]表⽰）数字or字母or姓名ect.任何元素都可以加⼊列表中，元素之间可以没有任何关系
bicycles = ['trek','cannondale','redline']
print(bicycles)
['trek', 'cannondale', 'redline']
访问列表元素（列表名称[元素索引]）
bicycles = ['trek','cannondale','redline']
print(bicycles[0])
trek
输出的结果更加整洁可使⽤title（）函数（列表名称[元素索引].title()）
print(bicycles[0].title())
Trek
元素索引从0开始⽽不是1，元素的最后⼀个指定为-1，倒数第⼆个元素-2.以此类推，在不知道列表长度的情况下可以访问最后的元素
bicycles = ['trek','cannondale','redline']
print(bicycles[-1].title())vba高级编程宝典
print(bicycles[0].title())
print(bicycles[1].title())
Redline
Trek
Cannondale
使⽤列表的值各个值
bicycles = ['trek','cannondale','redline']
message = "this is a new "+bicycles[0].title() + "."
print(message)
this is a new Trek.
作业：
3-1 姓名：将⼀些朋友的姓名存储在⼀个列表中，并将其命名为names 。依次访问该列表中的每个元素，从⽽将每个朋友的姓名都打印出来。
names = ["Bell","Peter","Alice","Ben"]
print(names[0])
print(names[1])
print(names[2])
print(names[3])
Bell
Peterpython入门教程(非常详细)书
Alice
Ben
3-2 问候语：继续使⽤练习3-1中的列表，但不打印每个朋友的姓名，⽽为每⼈打印⼀条消息。每条消息都包含相同的问候语，但抬头为相应朋友的姓名。
names = ["Bell","Peter","Alice","Ben"]
message = names[0]+ ", nice to meet you! "
print(message)
message = names[1]+ ", nice to meet you! "
print(message)
message = names[2]+ ", nice to meet you! "
print(message)
message = names[3]+ ", nice to meet you! "
print(message)
Peter, nice to meet you!
Alice, nice to meet you!
Ben, nice to meet you!
3-3 ⾃⼰的列表：想想你喜欢的通勤⽅式，如骑摩托车或开汽车，并创建⼀个包含多种通勤⽅式的列表。根据该列表打印⼀系列有关这些通勤⽅式的宣⾔，如“I would ways = ["bike","on foot","train"]
ways = ["bike","on foot","train"]
sayings = "I would like to own a Honda "+ ways[0]
print(sayings)
javascript中setinterval
sayings = "I like  "+ ways[1].title()
print(sayings)
sayings = "The "+ ways[-1] + " is fast!"
print(sayings)
I would like to own a Honda bike
I like  On Foot
The train is fast!
3.2 修改，添加和删除元素
修改列表元素
ways = ["bike","on foot","train"]
print(ways)
java安装教程及环境配置图片ways[0]="plane"
print(ways)
['bike', 'on foot', 'train']
sql条件查询['plane', 'on foot', 'train']
添加元素
列表末尾添加
ways = ["bike","on foot","train"]
ways.append('plane')
print(ways)
['bike', 'on foot', 'train', 'plane']
ways = []
ways.append('plane')
ways.append('on foot')
ways.append('bike')
ways.append('train')
print(ways)
['plane', 'on foot', 'bike', 'train']
列表中插⼊元素
insert(元素索引，元素)
ways = ["bike","on foot","train"]
print(ways)
ways.insert(0,'plane')
print(ways)
['bike', 'on foot', 'train']
['plane', 'bike', 'on foot', 'train']
从列表中删除元素
del语句
ways = ["bike","on foot","train"]
print(ways)
del ways[0]
print(ways)
['bike', 'on foot', 'train']
['on foot', 'train']
pop()函数        pop（弹出）：列表就像⼀个栈，⽽删除列表末尾的元素相当于弹出栈顶元素，按时间存储pop（）打印最后的
ways = ["bike","on foot","train"]
print(ways)
poped_ways = ways.pop()
print(ways)
print(ways)
print(poped_ways)
['bike', 'on foot', 'train']
['bike', 'on foot']
train
根据值删除元素
remove()  这个函数有啥⼦⽤呢？当你不知道要删除的元素的位置，只知道要删除的元素的值ways = ["bike","on foot","train"]
print(ways)
['bike', 'on foot']
amazing当我们将值从列表中删除时，还可以接着使⽤值
ways = ["bike","on foot","train"]
print(ways)
too_fast = "train"
print(ways)
print("The " + too_fast +" is fast.")
['bike', 'on foot', 'train']
['bike', 'on foot']
The train is fast.
元素从列表中删除时，但是它还储存在too_fast 中
注意啦：：：remove()只能删除第⼀个指定的值
ways = ["bike","on foot","train","train"]
print(ways)
print(ways)
['bike', 'on foot', 'train', 'train']
html下拉列表如何设置['bike', 'on foot', 'train']
组织列表
永久性排序
sort（），按字母顺序排序，永久性修改，⽆法恢复
ways = ["bike","on foot","train","car"]
ways.sort()
print(ways)
['bike', 'car', 'on foot', 'train']
与字母顺序相反的排序，久性修改，⽆法恢复
ways.sort(reverse=True)      向sort()传递reverse=True
ways = ["bike","on foot","train","car"]
ways.sort(reverse=True)
print(ways)
临时排序
sorted()函数能按特定的顺序显⽰元素，不影响它们在列表中的原始排序
ways = ["bike","on foot","train","car"]
print("Here are the ways:")
print(ways)
print("nHere are the ways:")
print(sorted(ways))
print("nHere are the ways:")
print(ways)
Here are the ways:
['bike', 'on foot', 'train', 'car']
['bike', 'on foot', 'train', 'car']
Here are the ways:
['bike', 'car', 'on foot', 'train']
Here are the ways:
['bike', 'on foot', 'train', 'car']
与字母顺序相反，向sorted()传递reverse=True
ways = ["bike","on foot","train","car"]
print("Here are the ways:")
print(ways)
print("nHere are the ways:")
print(sorted(ways,reverse=True))
print("nHere are the ways:")
print(ways)
Here are the ways:
['bike', 'on foot', 'train', 'car']
Here are the ways:
['train', 'on foot', 'car', 'bike']
Here are the ways:
['bike', 'on foot', 'train', 'car']
倒着打印列表
reverse()只是反转列表元素序列，永久改变了元素顺序，但可恢复，需对列表再次调⽤reverse（）ways = ["bike","on foot","train","car"]
print(ways)
print(ways)
['bike', 'on foot', 'train', 'car']
['car', 'train', 'on foot', 'bike']
确定列表的长度
len()函数，列表的长度
ways = ["bike","on foot","train","car"]
print(len(ways))
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