Next lesson: Start Python(Ii)

Installation and Preparation

  • mac osPython, my own pythonPython 2.7.16
  • windowsStudents, pleaseDownload the python
  • There is an editor that can write code or a TXT text editor (e.g.notepad++)

File execution mode

  • pythonThe file suffix is.pyFile naming, following all the way files are created
  • usepythonKeyword execution 
    CD Current python file directory python test.pyCopy the code
  • As self-executingpythonfile
    • The.py header file identifies the current executable file 
      #! /usr/bin/python
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    • Changes the current file to an executable file 
      Chmod +x File nameCopy the code

Basic debugging

  • printPrints the current running value

Add comment information

  • The new learning language, cannot leave the annotation, the way to add annotation
  • Single-line comments
    • #Before or at the end of the line#character
    # This is a line comment
print('I was output... ') # This is the code ready for output
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  • Multiline comment
    • ' ' ' or "" "Three single quotes in pairs, or three double quotes
    """ I'm the first line comment I'm the second line comment I'm the third line comment ""
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Sets the character encoding of the file

  • If you are in the print above, try to print Chinese and find an error
  • That’s right
  • To print non-ASCII characters, declare the type of the current file at the head of the file
# coding=utf-8
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Hello, python

  • Okay, now it’s time to say hello
# coding=utf-8
hello = 'hello'
print '%r %r' % (hello, 'Python')
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