Python Syntax :

First python program :

Python syntax can be executed by writing directly in the Command Line, or by creating a python file on the server, using the .py file extension, and running it in the Command Line.

Directly - Command Line :

  1. Open "DOS/CMD"
  2. type python command (active python language / Enter the python language)
  3. then type print("Hello, World") this code
  4. Hit Enter, Done!
python command line direct

.py file - Command Line :

  1. Open a Text Editor (Recommend: Notepad++)
  2. Write your code on the editor, and save it python installation directory with .py extention (my instalation directory "c:/python", you save it your python installation directory)
    python with notepad++
  3. Open "DOS/CMD" and change your directory. (example: cd: c:/python)
  4. Executable command is : python
  5. Hit Enter, Done!
python server .py extention command line

.py file double click run - Commend Line :

  1. Write scripts and save it with .py extention (Any location/directory/path) and we use: #Hello world! For comments and input("any key to exit...") use for hold the screen after executing the program) :
    python notepad++ direct run
  2. After save just double click the file, Done!
python double click to run

Note : Here we use input() function just for hold the screen after executing the program.

Python Comments :

In python language ( # ) sing use for comments, all characters after the # and up to the end of the physical line are part of the comment and the Python interpreter ignores them.

Example :

  1. #first comment
  2. print("Hello, Python!") #second comment
  3. #third comment

Output :

python comments with exit function

Note : We use print() function for showing some texts/values and exit() function use for exit from the python.

Docstrings / Multiple Line Comments :

Python also has extended documentation capability, called docstrings. Docstrings can be one line, or multiline. Following triple-quoted string is also ignored by Python interpreter and can be used as a multiline comments.

Example :

  1. """
  2. This is a
  3. multiline docstring.
  4. """
  5. print("Hello, python!")
  6. input()

Output :

python docstring comments

Multiple Statements on a Single Line :

The semicolon ( ; ) allows multiple statements on the single line given that neither statement starts a new code block. Here is a sample snip using the semicolon :

Example :

name = 'AyaN'; age='24'; print("My name is: " + name + "\n" + "My age is: " + age); input();

Output :

python semicolon and new line

Note : \n is help you create a new line.

Computer Science Engineering

Special Notes

It's a special area where you can find special questions and answers for CSE students or IT professionals. Also, In this section, we try to explain a topic in a very deep way.

CSE Notes