Python Basic Learning Notes

One, Python four types of data formats

Integers---- 2, 3,

Long integers: Refers to integers that are larger than

floating point---- 3.23, 52.3E E: The token represents a power of 10.

plural----( -5+4j), (2.3-4.6J)

Two, Python string

A single quotation mark: the single quote output string, and the string is left intact.

Input: ' What ' s your name ' Output:what ' s your name

b Double quotation marks: the same as single quotes, leaving the source string as is output.

C Three quotation marks ("' | ""): the output of a multiline string can be followed as indicated.

"This is a string

The second line

He said "You is good"

’’’

D escape character (\)

input "what\ s your name?"

output "What ' s your name?" "

E Natural string: Do not require special handling with the swivel chair character. The system is recognized by adding R or R directly before the string.

input:r "What ' s your name"

Output:what ' s your name

The F-string is immutable: Once your string is created, you can no longer change it.

G literal cascading string: If you put two strings in a literal order, Python will automatically connect them together.

input "What ' s" "Your Name"

Output what ' s your name.

Third, Python variables

Naming rules for variables: (1) The first character of a variable name must be either a character (uppercase or lowercase) or an underscore.

(2) Other parts can be letters (uppercase or lowercase), underscores, numbers.

(3) There is a difference between the uppercase and lowercase letters in the variable name.

Iv. specific examples of Python scripts.

(1) General input and output:

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(2) An example of an expression:

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(3) Examples of If/else statements:

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(4) example of a while statement:

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(5) For loop example:

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(6) An example of a break:

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(7) Continue usage Example:

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(8) Examples of functions in Python:

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(9) Examples of local variables use:

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(10) Examples of global variables use:

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The output is:

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Example of use of the return statement:

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Python Basic Learning Notes