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This article focuses on "how to quickly master the basic grammar of Python", interested friends may wish to take a look. The method introduced in this paper is simple, fast and practical. Let's let the editor take you to learn how to quickly master the basic grammar of Python.

1. Python coding

By default, Python source files are processed in UTF-8 encoding. In this encoding, characters from most languages in the world can be used simultaneously in string literals, variable or function names, and comments. Using UTF-8 coding method can better display simplified Chinese, traditional Chinese, Japanese and Korean and so on.

If you do not use the default encoding, to declare the encoding used by the file, the first line of the file is written with a special comment.

II. The line of python

A complete python program can be divided into many logical lines. A logical row consists of one or more physical rows concatenated explicitly or implicitly. The physical line is counted as a line at the end of the line Terminator, and python uses the standard C's traditional newline character, which is\ n, as the line termination flag.

Generally speaking, a physical line is a logical line. However, it can also be composed of multiple physical rows to form a logical row, which involves explicit and implicit splicing of rows.

1. Explicit line stitching

Two or more physical lines can be concatenated into a logical line using the backslash character (\). The rules are as follows: when a physical line ends with a backslash that is not in a string or comment, it will be spliced with the next line to form a separate logical line, and the backslash and subsequent newline characters will be deleted.

It should be noted that lines ending with a backslash cannot have comments, nor can backslashes concatenate comments.

2. Implicit line stitching

Expressions within parentheses (), square braces [], or curly braces {} are allowed to be divided into multiple physical lines without the need for a backslash.

Implicit line splicing can be annotated. The indentation of subsequent lines does not affect the program structure. Subsequent lines are also allowed to be blank.

3. Python blank line

A logical line that contains only spaces, tabs, feed characters, or comments will be ignored. However, blank lines are often used to split code blocks to facilitate code maintenance.

IV. Python indentation

A major feature of python is the use of indentation to represent code organization. Unlike other languages, some use {} or other forms to represent a block of code. However, indentation is not strictly limited, and you can use multiple spaces or the Tab key.

It is important to note that it is considered illegal to mix tab and space indentation in a source file so that determining the indentation level depends on the number of spaces corresponding to the tab; this situation will cause a TabError.

In other words, in a python file, if you use the Tab key, you will all use the Tab key. If you use 2 spaces, you will use 2 spaces, so there will be no problem. Generally speaking, you can use 4 space keys, and in pycharm, you can also set the input Tab key to enter 4 spaces.

5. Python comments

Comments are an interpretation of the program and cannot be run. In python, single-line comments begin with #, and multiline comments are enclosed in three single quotation marks ('') or three double quotation marks ("").

VI. Python identifier

Identifiers, or names, are described by the following lexical definitions. In the ASCII range (U+0001..U+007F), the characters that can be used for identifiers are the same as Python 2.x: uppercase and lowercase letters A to Z, underscore _, and numbers 0 to 9, but not with numbers.

Python 3.0 introduces extra characters outside the ASCII range (see PEP 3131). The classification of these characters uses the Unicode character database version included in the unicodedata module. There is no limit to the length of identifiers. Sensitive to case.

7. Python keyword

The following identifiers are used as reserved words or keywords of the language and cannot be used as general identifiers. The spelling of the keyword must be exactly the same as listed here.

8. Basic data types of python

The basic data types provided in Python are as follows:

Int (plastic surgery): for example, our 10meme 20 is an integer, which can represent tens, hundreds, tens of thousands, hundreds of millions, tens of billions, and so on.

Float (decimal type): often used to represent decimals such as 2.4, 5.0, etc.

Str (string type): any text enclosed in single or double quotation marks is called a string.

Bool (Boolean type): only two values, True and False, are used to indicate whether an expression is valid or not.

None (null type): note that the None type is not zero, and None and any other data type comparison always returns False.

So when we use basic types, we must follow the above requirements, otherwise the python interpreter will report an error.

At this point, I believe you have a deeper understanding of "how to quickly master the basic grammar of Python". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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