Sort the List

The List object in Python has a built-in sort() method that naturally sorts the elements of the List alphabetically/numerically in ascending order, as shown in the following code:


thislist = ["orange"."mango"."kiwi"."pineapple"."banana"]
thislist.sort()
print(thislist)

PS E:\dream\markdown\python> & "C:/Program Files (x86)/Python/python.exe" e:/dream/markdown/python/app/app.py
['banana'.'kiwi'.'mango'.'orange'.'pineapple']

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If the list is all numbers, the default is to sort the list in ascending order, as shown in the following code:


thislist = [100.50.65.82.23]
thislist.sort()
print(thislist)

PS E:\dream\markdown\python> & "C:/Program Files (x86)/Python/python.exe" e:/dream/markdown/python/app/app.py
[23.50.65.82.100]

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The List in descending order

In many cases, we also need to reverse. To reverse, we need to add reverse = True to sort() as follows:


thislist = ["orange"."mango"."kiwi"."pineapple"."banana"]
thislist.sort(reverse = True)
print(thislist)

PS E:\dream\markdown\python> & "C:/Program Files (x86)/Python/python.exe" e:/dream/markdown/python/app/app.py
['pineapple'.'orange'.'mango'.'kiwi'.'banana']

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In the same way, let’s look at a list of pure numbers.


thislist = [100.50.65.82.23]
thislist.sort(reverse = True)
print(thislist)

PS E:\dream\markdown\python> & "C:/Program Files (x86)/Python/python.exe" e:/dream/markdown/python/app/app.py
[100.82.65.50.23]

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Copy List

Note that Copy lists cannot simply use list2 =list1, so that list1 and list2 are the same reference, and modifying one List affects the other.

There are two ways to copy a list.

  • Use copy()

thislist = ["apple"."banana"."cherry"]
mylist = thislist.copy()
print(mylist)

PS E:\dream\markdown\python> & "C:/Program Files (x86)/Python/python.exe" e:/dream/markdown/python/app/app.py
['apple'.'banana'.'cherry']

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  • Use the list() function

Put an existing list into the constructor of a new list as follows:


thislist = ["apple"."banana"."cherry"]
mylist = list(thislist)
print(mylist)

PS E:\dream\markdown\python> & "C:/Program Files (x86)/Python/python.exe" e:/dream/markdown/python/app/app.py
['apple'.'banana'.'cherry']

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The List with

There are several ways to combine lists in Python.

  • Use the +.

This also seems to be unique to Python, with the following code:


list1 = ["a"."b"."c"]
list2 = [1.2.3]

list3 = list1 + list2
print(list3)

PS E:\dream\markdown\python> & "C:/Program Files (x86)/Python/python.exe" e:/dream/markdown/python/app/app.py
['a'.'b'.'c'.1.2.3]

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  • Use the append() function

Using the append() function to append each item in a collection individually to the new collection is a bit more cumbersome, as shown in the following code:


list1 = ["a"."b" , "c"]
list2 = [1.2.3]

for x in list2:
  list1.append(x)

print(list1)

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  • Use the extend() function

list1 = ["a"."b" , "c"]
list2 = [1.2.3]

list1.extend(list2)
print(list1)

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More List methods

There are a lot of methods in the List. You can operate other methods by yourself.

Link: www.w3schools.com/python/pyth…

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