Python Language Basics

Syntax

Blanks?

code "print ()", then exeut

Double quotes and single quotes

double quotes equal to single quotes

[] does not work to specify precedence in formula

() is used to specify precedence in formula rather than []

For example, ((1+r)*n-1) can be executed, but [(1+r)*n-1] can not be executed.

[] have other function, like range\[1:50\]

Multiplication operator * can not be omitted in formula

Take an example:

when we exercise the mortgage calculator: A=P*r*(1+r)
is different from A=Pr\(1+r\), the latter one can not be executed.

Where need to be bracket? Where need to be quotation mark?

Bracket is a function quote (e.g print () ); quotation mark is used to quote the string

Small p is different from capital P

p = 1
print(P)

You will see the error message NameError: name 'P' is not defined . That is because Python is case-sensitive. The lowercase p and uppercase P mean different variables.

() close to the range in the left, open the range in the right

For i in range(1,10):
print (i)

You will see the outcome: 1,2,3,4,5,6,7,8,9 without 10, because the left range is included, while the right range is excluded.

Self learning resources

//TODO: study the following pointers and add comments

这个不错，一一对应，清楚明白。 https://carolhsu.gitbooks.io/django-girls-tutorial-traditional-chiness/content/intro_to_command_line/README.html 不过这篇有一个地方补充一下： Windows进入command line的方法是： 开始菜单 — 在搜索栏打入“cmd” 。 （这篇是台湾的系统吧， 什么“命令提示字元”.[Dizzy].）