python-First day Learning python

1, Python language can use the development tools are: Charles, fiddles, etc...

2, language classification: compiled and interpreted type, compiled type such as: C, C + +, C # .... Interpreted type: Python, java, php .....

3. Set Python in Pycharm

Set fields such as

Git.exe must be placed in the installation directory \program Files (x86) \git\cmd\git.exe

3, import the Get file, as follows

4. Variables in the Python language

In the Python language, instead of adding a type to a variable like any other language, the variables in Python are simple enough to give a variable name and assign a value

such as: Name= "Zhang San" The type is a string type and "" defines

Age=20 the type is a data type

Output the following example

name= ' Zhang San '
age=20
money=20.5
price=10.22222
print ("My name is%s, this year%d, cash only%r, bought%.2f things."% ( Name,age,money,price))

The output in%s%d%r%s represents a dot character, and the output is a string type
%d represents a point character, and the output is a data type
%r represents a point character that is used when you do not know what type to output
And%.f, representing how many decimal places to follow, 2f is two decimal places, 3f is 3 decimal places, and so on

5. Shortcut keys in the Python language
ctrl+d Quick Copy Line
ctrl+/Quick Comment line, quick uncomment

6, the output, the use of single and double quotation marks
When to use single quotes, when to use double quotes
If there is a single quotation mark inside the sentence, use double quotation marks outside, if there is double quotation mark in the sentence, the outside is enclosed in single quotation marks, if there is a single quotation mark in the sentence, and there is double quotation mark, it is "" ' three single quotation mark
    Three quotation marks also have comments on the function ' ' ' comments, comments, notes ' 
Example: Let's go output syntax for print ("Let's Go")
I am a "little bird" output syntax for print (' I am a ' little bird ')
Let's go, the "tart" output syntax for print ("Let's Go," "The Sao Year")

7. Input Syntax
  input receives a string type and must be coerced if it needs to be converted to another type
Example: Name=input (' Please enter your name: ')
age=input (' Please enter your Age: ')
Age=int (age)
money=inptu (' Please enter your money: ')
can also be written directly as Age=int (input (' Please enter your name: '))
print (' My name is%s, age is:%d, how much money do you have:%s '% (Name,age,money))
can also be written in the following format
Print (name+ ' age is: ' +age+ ', ' +name+ ' has ' +money+ ' money ')

8. Judgment

All the judgments in Python are if-elif-else.

For example, the following determines the data type

Score=int (Input (' Please enter your score: '))
If Score>=60 and score<70:
Print (' Pass ')
Elif score>=70 and score<90:
Print (' Your grades in general ')
Elif score>=90:
Print (' Your Line of Excellence ')
Else
Print (' Your grades fail ')


And the judgment of the character type.
The character type equals "= =", not equal to "! ="
Name=input ("Please enter your name:")
If name== ' Zhang San ':
Print ("hahaha")
Else
Print ("hehe")


9. Circulation
Loops generally consist of two, while,for
While: A counter must be defined, the following example i=i+1 is equivalent to a counter
I=0
While i<5:
 Print (i)
   i=i+1

When a break is encountered in the loop, the loop is immediately ended
I=0
While i<5:
Print (i)
I=i+1
If i==2:
Break
The output is: 0, 1

Continue: End this cycle, inherit the next loop, example
I=0
While i<5:
I=i+1
If i==4:
Continue
Print (' Output result:%d '%i)   

python-First day Learning python