List (index and slice, additions and deletions), count, sort, ganso and ganso nesting

1. List

1. the list is compared to a string. data types are not restricted. and can store a lot of data.

2. representation: [] each item in square brackets is separated by commas

3. lists and strings, as well as indexes and slices

Common functions:

1. Add : Append () can only be added at the end of the list

　　　　2. Change : Remove()

　　　　3. Change : Index modification

　　　　4. Check : for Loop

Common methods:

　　　　1. Len () calculates the length of the string

　　　　2. count () find the number of "xxx" occurrences

　　　　3. sort () sorting

Index and slice cases for lists

Index:

Slice:

　　

two. Columns table additions and deletions to change

Increase　　  

　　

Delete　　 There ( pop, remove, clear, Del[delete] )

Pop the last string is deleted by default, You can also instruct the subscript to delete

　　

Remove　　 Specifies that deleted elements Delete elements that do not exist will cause an error

Clear Clear List ( List )

　　　

Slice Delete　　 del [m:n] Remove a range from the list

del [M:N]

　　

　　Change

Index, Slice modification

　　Check

Enquiry , column column table is ? an Iterative object , so you can go in ? for Loops

　　

Three. counting, sorting

Count　　 count ()

　　

　Sort: usually sort by numbers

sort () Ascending

sort (reverse = True) Descending

　　

Reverse Sequential Rollover [:: -1]

List nesting:

The use of reduced-dimensional operation, one layer to see

　　

Four . tuples and tuples nesting (tuple)

1.　　 tuples : commonly known as immutable lists . read-only lists, indexed and sliced, which can be used for any data type, can be queried. Loops can also be. Slices can also. But just can't change.

2. Presentation: () each item in parentheses is separated by commas

Note:

immutable is its inner child element. if the child element is a list. The elements in the list can be changed.

　　

Five. Range

Range can help us get to a set of data. This data can be obtained through a For loop

　　

　　

　　

List (index and slice, additions and deletions), count, sort, ganso and ganso nesting