笔记整理自《a byte of python(python3)》 (click here, read right now)
版本：python3.7
编辑器：PyCharm
系统：win10
中文大写为章节，小写阿拉伯为章节中节选内容(对应代码在程序块中可见)

一、Introduction

略

二、Dedication(各种推荐题词)

略

三、Preface(序言)

略

四、About Python

了解

五、Installation(安装)

自行安装

六、First Step

print（'Hello world'）

七、Basics

常量、数、字符串、单引、双引、三引 (略)
format方法
转移序列
原始字符串(自然字符串)
变量与文字常量使用

# 2018.3.7
# 2.format mathod
age = 20
name = 'Swaroop'
print('{0} was {1} years old when he wrote this book'.format(name, age))
print('Why is {0} playing with that python'.format(name))

# decimal (.) precision of 3 for float '0.333' 保留三位小数
print('{0:.3f}'.format(1.0/3))

# (^) to 11 width '___hello___' 位宽为11位的hello
print('{0:_^11}'.format('hello'))

# 'Swaroop wrote A Byte of Python'
print('{name} wrote {book}'.format(name='Swaroop', book='A Byte of Python'))

# print() always ends with an invisible "new line" like '\n', to prevent this, end with a blank or space
# 并不能在print()语句后再紧接着一个语句
print('a', end='')
print('b')
print('Hey', end=' ')
print("anybody else here?", end=' ')
print("Ah oh ?!")



# 2018.3.8
# 3.Escape Sequences \ and \t (most useful ones)

# What's your name ?
print("What's your name ?")  #double quote
print('What\'s your name ?') #single quote with an escape sequence \'

#"Taylor Swift", she said.
#print(""Taylor Swift", she said.") is wrong. Note to the single quote or double quote
print('\"Taylor Swift\", she said.') # \" print as "
print("\"Taylor Swift\", she said.") # \" print as "

# Escape Sequence is an \ before the quote or \ itself.
print('Escape Sequence is an \\ before the quote or \\ itself.') # \\ print as \

# tab \t
print('This is the first sentence. \t This is a sentence after a tab.')

# Note to the single quote and double quote
print("This is the first sentence. This is the second sentence.")
print('This is the first sentence. This is the second sentence.')

# note to the backslash, there's no new line
# This is the first sentence.This is the second sentence.
print("This is the first sentence.\
This is the second sentence.")


# 2018.3.12
# 4.Raw String
'''
Raw String: Specify some strings where no special processing
note to r in the second line:
第一句中\n为换行转义，编译后显示换行; 第二句中r去掉了\n的转义作用，结尾
的\n字符会显示出来
'''
print("New lines are indicated by \n")
print(r"New lines are indicated by \n")


# 2018.3.20
# 5.Using Variables and Literal Constants
'''
python中任何变量无需声明或类型定义
triple quote可以注释语句也可以对多行字符串引用
下面第二个语句块编译后为左对齐三行
'''
i=5
print(i)
i=i+1
print(i)

s='''This is a multi-line string.
This is the second line.
The third line.'''
print(s)

# 这两行任意一行结尾加或不加分号都不会影响结果(显示5)
i=5
print(i)

# 结果同样显示5。若在每行开始有缩进(indentation)，编译会报错(unexpected intend)
i=\
5
print(i)

【声明】本博文为学习笔记，含有个人修改成分，并非完全依照《a byte of python》，仅供参考。若发现有错误的地方，请不吝赐教，谢谢。同时，我也会不定期回顾，及时纠正。#

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