<a href="http://www.jianshu.com/p/54870e9541fc">总目录</a>
课程页面：https://www.codecademy.com/
内容包含课程笔记和自己的扩展折腾
Lists
- 例如：
list_sample = [1, 2, 3, "ZHANG Yong", "张雍"] - 和string一样，可以是空的：[]
- 和string一样，也有index，从0开始。
print list_sample[4]Output: 张雍 - 可以替换list里面的items，譬如把sample list里面的3换成"ZY"：
list_sample[2] = "ZY" -
增加 item：
.append():
list_sample.append(6)# [1, 2, 3, "ZHANG Yong", "张雍", 6] - 和string一样，也有长度：
len() - 和string一样，也能部分获取：
list_sample[n:m] -
询问index:
list.index(item)譬如询问"张雍"的index：
print list_sample.index("张雍")Output: 4 -
插入指定位置：
list.insert(index, item)
list_sample = [1, 2, 3, "ZHANG Yong", "张雍"]
list_sample.insert(1, 1.5)
# 就变成了：[1, 1.5, 2, 3, "ZHANG Yong", "张雍"]
-
排序：
list.sort()
#sort list_A in alphabetical order
list_A = ["cool", "astronaut", "zebra", "xenophobia", "recursive"]
list_A.sort()
print list_A
Output:
['astronaut', 'cool', 'recursive', 'xenophobia', 'zebra']
- **移除item(s): **
list.remove(item)
list_A = ["cool", "astronaut", "zebra", "xenophobia", "recursive"]
list_A.remove("cool")
print list_A
Output:
['astronaut', 'zebra', 'xenophobia', 'recursive']
For loop
例0：String Looping
string也是可以loop的：
for x in "ZHANG_Yong"
print x
Output:
Z
H
A
N
G
_
Y
o
n
g
Process finished with exit code 0
例1：打印出列表中都有哪些items：
list_sample = [1, 2, 3, "ZHANG Yong", "张雍"]
for x in list_sample:
print "%s is in this list" % x
Output:
1 is in this list
2 is in this list
3 is in this list
ZHANG Yong is in this list
张雍 is in this list
例2：listA是数字，输出其平方，且按照大小排序：
listA = [6, 7, 1, 9, 0]
listB = []
for x in listA:
listB.append(x**2)
listB.sort()
print listB
Output:
[0, 1, 36, 49, 81]
例3：多个lists作为arguments
list_A = [3, 9, 17, 15, 19]
list_B = [2, 4, 8, 10, 30, 40, 50, 60, 70, 80, 90]
for a, b in zip(list_A, list_B):
print max(a, b)
Console:
3
9
17
15
30
Dictionaries
- 和string&list一样，可以是空的：{}
-
key-value pairs / tuples: 然后就能通过比较好记的key拿到对应的value
{key : value, key2 : value2, ...}
d = {"birthday_day" : "1st", "birthday_month" : "June"}
print d["birthday_day"]
Output:
1st
-
增加tuples: (和往list里面加items类似）
dictionary[new_key] = new_value
d = {"birthday_day" : "1st", "birthday_month" : "June"}
d["fav_fruit"] = "orange"
print d
Output:
{'birthday_month': 'June', 'birthday_day': '1st', 'fav_fruit': 'orange'}
- value可以是list:
d = {"birthday_day" : "1st", "birthday_month" : "June"}
d["fav_fruit"] = ["orange", "avocado", "banana"]
print d
Output:
{'birthday_month': 'June', 'birthday_day': '1st', 'fav_fruit': ['orange', 'avocado', 'banana']}
- **len(d): **多少个tuples
-
删除tuple：
del dictionary[key] - 更改value： `dictionary[key] = new_value
- curly braces 之间可以断行：
d = {
'birthday_month': 'June',
'birthday_day': '1st',
'fav_fruit': ['orange', 'avocado', 'banana']
}
- grab an item from a list in a dictionary
# grab my first two fav food
d = {
'birthday_month': 'June',
'birthday_day': '1st',
'fav_fruit': ['orange', 'avocado', 'banana']
}
print d["fav_fruit"][:2]
Output:
['orange', 'avocado']
- for loop and dictionary:
d = {
'fav_fruit': ['orange', 'avocado', 'banana'],
'birthday_month': 'June',
'birthday_day': '1st',
}
# 注意上面dictionary里面tuples的顺序
for x in d:
print x + ":", d[x]
Output:
birthday_month: June
birthday_day: 1st
fav_fruit: ['orange', 'avocado', 'banana']
注意这里的顺序
