《Python for Beginners》学习笔记（5）

《Python for Beginners》为LearnStreet上的Python入门课程。本节主要学习内容为Lists and Tuples。

Lesson 6 Lists and Tuples

1. Length of List
计算List变量的长度。

1 def run(var):
2     #return your code here
3     return len(var)
4 
5 #This is just for you to see what happens when the function is called
6 print run([1,2,3,4,5])

输出结果：
5

2. Removing Elements of a List
移除列表中的某个元素。

days = ["funday","sunday","monday","tuesday","wednesday","thursday","friday"]
days.pop(0)
注意：pop(0)使用的是圆括号。

3. Appending Lists
在列表末尾添加元素。
days.append("saturday")
其中，days为List类型变量。

4. Concatenating Lists
连接两个列表。

1 def run(first, second):
2     #your code here
3     return first + second
4 
5 #This is just for you to see what happens when the function is called
6 print run([1,2,3],[4,5,6])

输出结果：
[1, 2, 3, 4, 5, 6]

5. Tuples
创建tuple变量使用圆括号而不是方括号，tuple类型的变量值是不可变的。
例如：tup = (10, 20, 30)

1 def run():
2     #your code here
3     name = ("Guinevere", 9102)
4     return name
5 
6 #This is just for you to see what happens when the function is called
7 print run()

输出结果：
('Guinevere', 9102)

6. 复习练习

 1 # assume lst is a list and tup is a tuple
 2 def run(lst, tup):
 3     #your code here
 4     if lst[1] == tup[1]:
 5         return tuple(lst) == tup
 6     else:
 7         return "not equal"
 8 
 9 #This is just for you to see what happens when the function is called
10 print run([1,2,3],(1,2,3))

输出结果：
True

注意：类型转换tuple(lst)

总结：
tuple和list是两种不同的数据类型，他们永远不会相等。但是他们内部的元素都是string类型，可以进行比较。