python函数和常用模块（二）,Day4

callable() # 是否可以被执行,是否可以被调用
chr() # ascii转字符
ord() # 字符转ascii
compile() # 编译
eval() # 执行
exec() # 执行
dict()
dir() # 快速查看对象为提供了哪些功能
help() #
divmod() #输出(商，余数)
isinstance() # 判断对象是否是某个类的实例
filter() # 函数返回True 将元素添加到结果中
map() # 函数的返回值添加到结果中
float() #
format() #
frozenset() #
globals() # 所有的全部变量
localse() #所有的局部变量
hash() # 生成哈希值
id() # 查看内存地址
issubclass() # 查看一个类是不是它的子类（派生类）
iter() #
len() # 查看长度 "李杰"3.x 长度为2（按字符计算）2.7.x中 长度为6 按字节计算
max()
min()
sum()
memoryview() # 跟内存地址相关的一个类
iter()
next()
object() # 一个类
pow() # 次方
property()
range()
repr()
reversed() # 反转
round() # 四舍五入
slice() #
sorted # 排序
vars() # 当前模块有哪些可以调用？
zip() # 实例 ：随机验证码
improt random
random.randrange(1,5)import random
r = random.randrange(65, 91)
li = []
for i in range(6):
r = random.randrange(0, 5)
if r == 2 or r == 4:
temp = random.randrange(0, 10)
li.append(str(temp))
else:
temp = random.randrange(65, 91)
c = chr(temp)
li.append(c)
result = "".join(li)
print(result)

1. 定义函数，为调用，函数内部不执行
2. 函数名 > 代指函数 @ + 函数名
功能：
1. 自动执行outer函数并且将其下面的函数f1当做参数传递
2. 将outer函数的返回值，重复赋值给f1

tpl = "i am {}, age {}, {}".format("seven", 18, 'alex')
print(tpl)
tpl = "i am {}, age {}, {}".format(*["seven", 18, 'alex'])
print(tpl)
tpl = "i am {0}, age {1}, really {0}".format("seven", 18)
print(tpl)
tpl = "i am {0}, age {1}, really {0}".format(*["seven", 18])
print(tpl)
tpl = "i am {name}, age {age}, really {name}".format(name="seven", age=18)
print(tpl)
tpl = "i am {name}, age {age}, really {name}".format(**{"name": "seven", "age": 18})
print(tpl)
tpl = "i am {0[0]}, age {0[1]}, really {0[2]}".format([1, 2, 3], [11, 22, 33])
print(tpl)
tpl = "i am {:s}, age {:d}, money {:f}".format("seven", 18, 88888.1)
print(tpl)
tpl = "i am {:s}, age {:d}".format(*["seven", 18])
print(tpl)
tpl = "i am {name:s}, age {age:d}".format(name="seven", age=18)
print(tpl)
tpl = "i am {name:s}, age {age:d}".format(**{"name": "seven", "age": 18})
print(tpl)
tpl = "numbers: {:b},{:o},{:d},{:x},{:X}, {:%}".format(15, 15, 15, 15, 15, 15.87623, 2)
print(tpl)
tpl = "numbers: {:b},{:o},{:d},{:x},{:X}, {:%}".format(15, 15, 15, 15, 15, 15.87623, 2)
print(tpl)
tpl = "numbers: {0:b},{0:o},{0:d},{0:x},{0:X}, {0:%}".format(15)
print(tpl)
tpl = "numbers: {num:b},{num:o},{num:d},{num:x},{num:X}, {num:%}".format(num=15)
print(tpl)

* py：模块
* 其他：类库1. 内置模块
2. 自定义模块
3. 第三方模块
安装：
* pip3
* 源码* 先导入
* 再使用可以是文件
可以是文件夹

#导入json模块
import json# 将python基本数据类型转换成字符串形式
json.dumps()
# 将python字符串形式转换成基本数据类型
json.loads()
# 将python基本数据类型转换成字符串形式,并写入文件
json.dump()
# 读取文件字符串，字符串形式转换成基本数据类型
json.load()通过loads()反序列化时，一定要使用""# 例
import jsondic = {'k1': 'v1'}
print(dic, type(dic))
# 将python的基本数据类型转换成字符串形式
result = json.dumps(dic)
print(result, type(result))# 将python字符串形式转换成基本数据类型
s1 = '{"k1": 123}'
dic1 = json.loads(s1)
print(dic1, type(dic1))li = [11, 22, 33]
json.dump(li, open('db', 'w'))li = json.load(open('db', 'r'))
print(li, type(li))

import pickle
li = [11, 22, 33]
r = pickle.dumps(li)
print(r)
restult = pickle.loads(r)
print(restult)pickle.dumps()
pickle.loads()
pickle.dump()
pickle.load()

# time module
print(time.clock()) # 返回处理器时间 3.3开始废弃
print(time.process_time()) # 返回处理器时间 3.3开始废弃
print(time.time()) # 返回当前系统时间戳
print(time.ctime()) # 输出Wed Sep 14 16:16:10 2016, 当前系统时间
print(time.ctime(time.time()-86640)) # 将时间戳转为字符串格式
print(time.gmtime(time.time()-86640)) # 将时间戳转换struct_time格式
print(time.gmtime())
print(time.localtime()) # 将时间戳转换struct_time格式,但返回的是本地时间
print(time.mktime(time.localtime())) # 与time.localtiem()功能想反，将struct_time格式转回时间戳格式
# time.sleep(4)
print(time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
print(time.strptime("2016-09-14", "%Y-%m-%d"))

# datetime module
print(datetime.date.today()) # 输出格式2016-09-14
print(datetime.date.fromtimestamp(time.time())) # 输出格式2016-09-14 时间戳转成日期
current_time = datetime.datetime.now()
print(current_time) # 输出格式2016-09-14 17:53:24.499480
print(current_time.timetuple()) # 返回struct_time格式print(current_time.replace(2014, 9, 12)) # 输出2014-09-12 18:17:20.264601 返回当前时间，但是指定值将被替换str_to_date = datetime.datetime.strptime("21/11/06 16:30", "%d/%m/%y %H:%M")
print(str_to_date)print(datetime.datetime.now() + datetime.timedelta(days=10)) # 比现在加10天
print(datetime.datetime.now() + datetime.timedelta(days=-10)) # 比现在减10天
print(datetime.datetime.now() + datetime.timedelta(hours=10)) # 比现在加10小时
print(datetime.datetime.now() + datetime.timedelta(seconds=120)) # 比现在加120秒

import logging
# 打印输出日志
logging.warning("user [alex] attempted wrong password more then 4 times")
logging.critical("server is down")# 将级别高于等于info的 写入日志文件
logging.basicConfig(filename='example.log', level=logging.INFO)
logging.debug('This message should go to the log file')
logging.info('So should this')
logging.warning('And this, to')logging.basicConfig(filename='example.log', level=logging.INFO, format='%(asctime)s %(message)s',
datefmt='%m/%d/%Y %I:%M:%S %p')
logging.debug('This message should go to the log file')
logging.info('So should this')
logging.warning('And this, to')