(Self-developed artificial intelligence) pythony list, artificial intelligence pythony

(Self-developed artificial intelligence) pythony list, artificial intelligence pythony

How to Create a list:

A = [1, 2, 3, 4, 5]

In this way, the elements in the element enclosed by brackets are separated by commas. This form represents a list.

Common Operations in the list:

1. Element assignment:

A [0] = 10

Add a 10 value at the position where the index of the List is 0 and overwrite the original 1.

Result: a = [10, 2, 3, 4, 5]

2. Add the following elements:

A. append (6)

Here we use the append () method to add a new object at the end of the list.

Result: a = [,]

3. Delete elements:

Del a [0]

Here, we use del to delete the element whose index is 0.

Result: a = [2, 3, 4, 5, 6]

Common methods in the list:

1. append:

A. append (7) # Add a new object to the end of the list

 

2. count:

A. count (2) # count the number of times 2 appears in List

 

3. pop:

A. pop () # remove the last element from the list by default, and return the value of this element. a. pop (3) # Remove the element from the specified position and return the value of this element.

 

4. insert:

A. insert () # insert 10 at the position where the index value is 2. Add 1 to the element on the original index 2 and the element index after the index.

 

5. remove:

A. remove (10) # remove the first match from index 0

 

6. sort:

A. sort () # sort in ascending order by default

 

Use the reverse parameter:

A. sort (reverse = True) # sort in reverse order

 

The string can use key = len:

A. sore (key = len) # sort by string from short to long a. sore (key = len, reverse = True) # sort by string from long to short