函数分为自定义函数和内置函数
python内置函数分类:
v = 55
v1 = float(55)
print(v1) #55.0
#示例:
a,b = divmod(1001,5)
print(a,b) #a=200,b=1
# 练习题 请通过分页对数据进行展示
"""
要求:
每页显示10条数据
让用户输入要查看的页面:页码
"""
USER_LIST = []
for i in range(1,836):
temp = {'name':'你-%s' %i,'email':'123%s@qq.com' %i }
USER_LIST.append(temp)
# 数据总条数
total_count = len(USER_LIST)
# 每页显示10条
per_page_count= 10
# 总页码数
max_page_num,a = divmod(total_count,per_page_count)
if a>0:
max_page_num += 1
while True:
pager = int(input('要查看第几页:'))
if pager < 1 or pager > max_page_num:
print('页码不合法,必须是 1 ~ %s' %max_page_num )
else:
start = (pager-1) * per_page_count
end = pager * per_page_count
data = USER_LIST[start:end]
for item in data:
print(item)
v = pow(2,3) #相当于2**3
print(v) # 8
v = round(1.127,2) #第二个数代表保留几位小数,默认是None
print(v) # 1.13 四舍五入
# 二进制转化成十进制
v1 = '0b1101'
result = int(v1,base=2) #base=2说明读取的是二进制
print(result)
# 八进制转化成十进制
v1 = '0o1101'
result = int(v1,base=8)
print(result)
# 十六进制转化成十进制
v1 = '0x1101'
result = int(v1,base=16)
print(result)
#1字节等于8位
# IP: 192.168.12.79 -> 001010010 . 001010010 . 001010010 . 001010010
# 请将 ip = "192.168.12.79" 中的每个十进制数转换成二进制并通过,连接起来生成一个新的字符串。
ip = "192.168.12.79"
ip_list = ip.split('.') # ['192','168','12','79']
result = []
for item in ip_list:
result.append(bin(int(item)))
print(','.join(result))
#应用:生成随机验证码
import random # 导入一个模块
def get_random_code(length=6):
data = []
for i in range(length):
v = random.randint(65,90)
data.append(chr(v))
return ''.join(data)
code = get_random_code()
print(code)
#示例:
v1 = [11,22,33,44]
result = map(lambda x:x+100,v1)
print(list(result))
#示例:
v1 = [11,22,33,'asd',44,'xf']
def func(x):
if type(x) == int:
return True
return False
result = filter(func,v1)
print(list(result))
# 用lambda表达式:
result = filter(lambda x: True if type(x) == int else False ,v1)
print(list(result))
# 相当于:
result = filter(lambda x: type(x) == int ,v1)
print(list(result))
import functools
v1 = ['wo','hao','e']
def func(x,y):
return x+y
result = functools.reduce(func,v1)
print(result)
# 用lambda表达式:
result = functools.reduce(lambda x,y:x+y,v1)
print(result)
class Foo:
pass
obj = Foo()
if type(obj) == Foo:
print('obj是Foo类的对象')
class Base:
pass
class Base1(Base):
pass
class Foo(Base1):
pass
class Bar:
pass
print(issubclass(Bar,Base))
print(issubclass(Foo,Base))
class Base(object):
pass
class Foo(Base):
pass
obj = Foo()
print(isinstance(obj,Foo)) # 判断obj是否是Foo类或其基类的实例(对象)
print(isinstance(obj,Base)) # 判断obj是否是Foo类或其基类的实例(对象)
class Base(object):
def func(self):
super().func() # 根据self对象所属类的继承关系,按照顺序挨个找func方法并执行(找到第一个为止)
print('base.func')
class Bar(object):
def func(self):
print('bar.func')
class Foo(Base,Bar): # Foo -> Base -> Bar
pass
obj = Foo()
obj.func()