Python编程从入门到实践笔记——变量和简单数据类型

#coding=gbk
#变量
message_1 = ‘aAa fff‘
message_2 = ‘hart‘
message_3 = "Albert Einstein once said, “A person who never made a mistake never tried anything new.”"

#使用方法修改字符串的大小写
print(message_1.title())
print(message_1.upper())
print(message_1.lower())

#字符串拼接
print(message_1+" "+message_2)

#使用制表符或换行符来添加空白
print("\tPython")
print("Python\nJava\nJavaScript")

#删除空白
#删除字符串末尾空白rstrip()
#删除字符串开头的空白lstrip()
#删除字符串两端的空白strip(),效果等于Java中的trim()
favorite_language=‘\tpython  ‘
print("My favorite language is "+favorite_language.rstrip()+".")
print("My favorite language is "+favorite_language.lstrip()+".")
print("My favorite language is "+favorite_language.strip()+".")

#字符串替换
a=‘Hello World‘
b=a.replace(‘World‘,‘Python‘)

#整数
num=23
print(num)

#**表示乘方运算
print(num**2)

#浮点数
num_1=0.1
print(num_1*2)

#使用str()避免类型错误
print(str(23)+"james")