List and tuples in Python

Common operations: Index, Shard, add, multiply, check whether an element belongs to a member of a sequence, length, minimum, maximum

Example:

numbers=[100,34,67# return value is 3# return value is#  return value is

List :

1. List function

>>>list ('Hello') ['H','E  ','l','l','o  ']

* You can use join (for example: ". Join (Somelist)) to convert a list of components into a string

2, the operation of the list

Element Assignment Value:

>>>x=[1,2,3]>>>x[1]=4>>>x[1,4,3]

To delete an element:

 >>>x=[ " abc  " ,  " def   ", "  ghi   ", "  JK  Span style= "COLOR: #800000" > " "  >>> del  x[2]  >>> x[  " abc   ", "   def   ", "   JK   "] 
 

Shard Assignment:

>>>x=list ('Happy')>>>name['H','a','P','P','y']>>>x[1:]=list ('Ello')>>>x['H','e','L','L','o']

3. List method:

Append

>>>x=[1,2,3]>>>x.append (4)>>>x[1,2,3,4]

Count

>>>x=[1,2,3,1,3,5,5]>>>x.count (3)2

Extend

>>>a=[1,1]
>>>b=[2,3]
>>>a.extend (b)
>>>a
[1,1,2,3]

Index

>>>x=[' A ', ' B ', ' C ']>>>x.index (' B ')
1

Insert Insertion Element

>>>x=[1,2,3]>>>x.insert (2, ' a ')
>>>x
[Up, ' a ', 3]

Pop removes the list element (the last one by default)

>>> x=[1,2,3,4]>>> x.pop ()4>>> x.pop (1)2>>> x[ 1, 3]

Remove removes the first occurrence of a value in the list

>>> x=['my',' to',' is','She',' to']>>> X.remove (' to')>>>x['my',' is','She',' to']

Reverse to store elements in the list in reverse

>>> x=[1,2,3]>>> x.reverse ()>>> x[3, 2, 1]

>>> x=[1,2,3]>>> list (reversed (x)) [3, 2, 1]>>> x[ 1, 2, 3]

Sort for sorting the list at the original location

>>> x=[4,6,2,1,7,8,3]>>> x.sort ()>>> x[1, 2, 3, 4, 6, 7, 8]
    >>> x=[4,6,2,1,7,8,3]>>> y=sorted (x)>>> x[4, 6, 2, 1, 7, 8, 3< c7>]>>> y[1, 2, 3, 4, 6, 7, 8]>>> x=[3,2,1]>>> y=x
     >>> y.sort ()>>> x[1, 2, 3]>>> y[1, 2, 3]

>>> sorted (' Hello ')
[' E ', ' h ', ' l ', ' l ', ' O ']

Tuples : Non-changing sequences

>>>(1, 2, 3)>>> (1,2, 3)# empty tuples ()>>> 1, syntaxerror:invalid syntax>>> 1, (1,)#  Ganso must have commas (1,)>>> 40+2 (42, 42, 42)

The tuple function transforms a sequence into a narimoto group

>>> tuple ([3,2,1]) (3, 2, 1)>>> tuple ('abc')(  'a'b'c')

Reasons for the non-substitution of tuples

• Tuples can be used as keys in the map
• Tuples exist as return values for many of the built-in functions and methods

List and tuples in Python