python之前期常用的内置函数

1.常用的内置函数

# 掌握
# res='你好'.encode('utf-8') 编码                                                      encode  编码
# print(res)
#
# res=bytes('你好',encoding='utf-8') 跟上面一样
# print(res)


# 参考ASCII表将数字转成对应的字符   
# print(chr(65))                                                                                    chr      ASCLL表 数字转换字符
# print(chr(90))
# 参考ASCII表将字符转成对应的数字
# print(ord('A'))                                                                                    ord      ASCLL表 字符转换数字 


# print(divmod(10,3))   10除3  取整数和余数部分                                divmod   10除3  取整数和余数部分




# l=['a','b','c']
# for item in enumerate(l):
#     print(item)


# l='[1,2,3]'              适用于读文件内容
# l1=eval(l)                                                                                                eval    将字符串中的表达式取出来
# print(l1,type(l1))     将字符串中的表达式取出来 
# print(l1[0])


# with open('a.txt',encoding='utf-8') as f:
#     data=f.read()
#     print(data,type(data))
#     dic=eval(data)
#     print(dic['sex'])


# print(pow(3,2,2)) # (3 ** 2) % 2  #3的2次方 除2取余                                pow    


# print(round(3.3)) 四舍五入                                         round    四舍五入


# print(sum(range(101)))   求和                                                              sum        求和

c = [-10,-5,0,5,3,10,15,-20,25]

                                                                                                                                                 min  最小值

print c.index(min(c))  # 返回最小值                                                                                    max    最大值    

print c.index(max(c)) # 返回最大值

print (min(80, 100, 1000))   取最小值






module=input('请输入你要导入的模块名>>: ').strip() #module='asdfsadf'   
m=__import__(module) 模块导入
print(m.time())
 

 

# 了解
# print(abs(-13))        负数变正数                                                        abs
# print(all([1,2,3,]))  判断列表所有bool值全部真返回真                        all
# print(all([])) 返回true

        
# print(any([0,None,'',1])) 有一个为真就就为真                                    any
# print(any([0,None,'',0])) 空就是false
# print(any([])) false


# print(bin(3)) #11       十进制转换二级制                                            bin
# print(oct(9)) #11 十进制转换八级制                                oct
# print(hex(17)) #11 十进制转换十六级制                            hex


# print(callable(len))    判断函数是是否可以被调用                              callable


# import time
# print(dir(time)) #列举出模块所有:time.名字                                    dic




# s=frozenset({1,2,3}) # 不可变集合                                        frozenset
# s1=set({1,2,3}) # 可变集合                                                            set


# a=1111111111111111111111111111111111111111111111
# # print(globals())   查看全局作用域名字                                            globals
# # print(locals()) 查看局部作用域名字                                       locals
# def func():
#     x=222222222
#     # print(globals())
#     print(locals())
# func()


# hash([1,2,3])


# def func():
#     """
#     文档注释
#     :return:
#     """
#     pass
#
# print(help(func))          查看帮助                                                            help