python入门4 python查看数据类型及类型转换

#coding:utf-8

#/usr/bin/python

"""

2018-11-03

dinghanhua

查看数据类型，类型转换

"""

"""查看数据类型type()"""

print(type(1),type(3.14),

      type('a'),type('abd'),

      type((1,2,3)),type(True),type(None),

      type([]),type({1,2}),type({1:'monday',2:'tuesday'}))

"""强制类型转换"""

"""整数，浮点数，ascii码转换：int(),float(),chr(),ord()"""

f = 3.14

print('f=%f,int(f)=%d '%(f,int(f)))

print(float(int(f)))

print(chr(65)) #整数转化为ascii码字符

print(ord('a')) #ascii字符转化为整数

'''转成布尔类型 bool()'''

print(bool(''),bool(''),bool([0])) #True

print(bool(''),bool(0),bool([]),bool(()),bool({})) #False

'''字符串 str()'''

print(type(str(f)))

'''特殊字符-转义字符 r忽略转义字符'''

print('abc\nghigk\tjfwejf\\fjewfjoewjfjfwejgwe\'jfwifoe?')

print(r'abc\nghigk\tjfwejf\\fjewfjoewjfjfwejgwe\'jfwifoe?')

print('c:\\user\\pycharm') #\\转义\

print(r'c:\user\pycharm') #用r无需加转义

print("i'm busy") #里面带'的用"

print('he said:"ok"') #里面带"用'