安装

语法

Strings 字符串

用引号包起来 Python中单引号'和双引号"没区别
用三个单引号'''或三个双引号"""可以直接print多行字符串而不必使用\转义符
字符串可以用+连接，用*重复 字符串后面用[]实现切片功能

print('''Hello World!
'''*3)

Hello World!
Hello World!
Hello World!

print('''Hello
'''+input('''what's your name?''') )

what's your name?yanwei
Hello
yanwei

len(string)

get the length of the string 获得字符串长度

print(len(input('''What's your name?''')))

What's your name?yanwei
6

Variables 变量

下面的内容效果很上面的一样

name = input('''what's your name?''')
length = len(name)
print(length)

Numbers

Integer

Float

round(float,n)

n代表小数点后面的位数

Booleans

Arithmetic Operators

Operator	Name
+	Addition
-	Subtraction
/	Divsion
%	Modulus
**	Exponentiation
//	Floor division

F Strings

以f或F开头 ，用{}把变量包起来

person = {'name':'yanwei','age':20}
print(f"The person is {person['name'].title()},aged {person['age']}.")

The person is Yanwei,aged 20.

if_else

a = int(input("输入整数a的值"))
b = int(input("输入整数b的值"))
if b > a:
  print("b is greater than a")
else:
  print("b is not greater than a")

Comparison Operators

Operator	Meaning
>	Greater than
<	Less than
>=	Greater than equal to
<=	Less than equal to

Logical Operators

and or not

Lists

list.index()

Returns the index of the first element with the specified value

fruits = ['apple','banana','cheery']
print(fruits.index('cheery'))

2

for loop with lists

fruits = ["apple", "banana", "cherry"]
for x in fruits:
  print(x)

apple
banana
cherry

while loop

i = 1
while i < 6:
  print(i)
  i += 1

1
2
3
4
5

Functions

def my_function(something):
  #Do this with something
  #Then do this

my_function(123)

something is parameter 123 is argument The parameter is the name of the data that's being passed in ,The argument is the actual value of the data.

Virtual Environment 虚拟环境

新建虚拟环境

python -m venv /path/to/new/virtual/environment

激活虚拟环境

source /path/to/new/virtual/environment/bin/activate

reference

https://docs.python.org/