Python data type

Basic data types

1. Digital

int (integral type)

On a 32-bit machine, the number of integers is 32 bits and the value range is 2**31-2**31-1, which is -2147483648~2147483647
On a 64-bit system, the number of integers is 64 bits and the value range is -2**63~2**63-1, which is -9223372036854775808~9223372036854775807

Long (integer)

Unlike the C language, Python's long integers do not refer to the positioning width, that is, Python does not limit the size of long integer values, but in fact, because of limited machine memory, we use a long integer value can not be infinite.

Float (float type)

Working with real numbers, which are numbers with decimal points

2. Boolean value

True or False

1 or 0

3. String

" Hello World "

String Common functions:

• Remove whitespace
• Segmentation
• Length
• Index
• Slice

4. List

To create a list:

1 name_list = ['DD','one',' boy ' ' ]2# or 3 name_list = list (['DD' ,'one','boy')

Basic operation:

Index

Slice

Additional

Delete

Length

Cycle

Contains

5, Ganso

To create a meta-ancestor:

1 dd = (11,22,33,44)2# or 3 DD = tuple ((11,22,33,44))

Basic operation:

Index

Slice

Cycle

Length

Contains

6. Dictionary (unordered)

To create a dictionary:

1person = {"Key":"value","name":" -"}2 #or3Person = Dict ({"Key":"value","name":" -"})

Common operations:

Index

New

Delete

Key, value, key-value pairs

Cycle

Length

7. Set Set

Set set, which is an unordered and non-repeating collection of elements

View Code

Operator

1. Arithmetic arithmetic

2. Comparison operation

3. Assignment operation

4. Logical operation

5. Member arithmetic

Other

1. For loop

Iterates through the contents of an object in order,

Ps:break, continue

DD = [11,22,33] for in DD:    print(i)

2, Enumerate

Add an ordinal to an iterative object

1 dd = [11,22,33]2 for in Enumerate (DD, 1):3     Print(k,v)

3. Range and Xrange

Specify a range of values to generate the specified number

Python data type