Python next day-list basic features

1. How to define alist

arr=["ABC","def","ghi"  ]

2.Append Method-Append elements to the tail of the list

arr=["ABC","def","ghi"] Arr.append ("jkl")print(arr);

The results are:[' abc ', ' Def ', ' Ghi ', ' JKL ']

3. Clear Method-Clears all data in the list

arr=["ABC","def","ghi"] Arr.clear ()print(arr);

The result is: []

4. Copy Method-copies all the elements in the list to the other list

arr=["ABC","def","ghi"] ARR2=arr.copy ()print(ARR2);

The result:[' abc ', ' Def ', ' Ghi ']

5.count("") Method--count the number of occurrences of the specified element in the list

arr=["ABC","def","ABC"] Count=arr.count ("ABC")print(count);

The result is: 2

6.Extend() appends all elements of a list to the specified list tail

arr=["ABC","def","ABC"] List2=["123","456","789  "]arr.extend (list2)print(arr);

The results are:[' abc ', ' Def ', ' abc ', ' 123 ', ' 456 ', ' 789 ']

7.index()--Gets the position of the first occurrence of the specified element in the list

arr=["ABC","def","ABC"  ]index=arr.index ("ABC")print(index);

The result is:0

8.Insert ()--Specifies the position of the subscript specified in the list to insert the element

arr=["ABC","def","ABC"] Arr.insert (0," hello ")print(arr);

The result is:[' Hello ', ' abc ', ' Def ', ' abc ']

9.Pop() removes the last element from the specified list

arr=["ABC","def","ABC"] Arr.pop (); Print (arr);

The result is:[' abc ', ' Def ']

Remove ()--Removes the element that is the first occurrence of the specified element in the list from left to right

arr=["ABC","def","ABC"] Arr.remove ("ABC"); Print (arr);

The result is:[' def ', ' abc ']

Reverse()--will specify the list flip order

arr=["1","2","3"] Arr.reverse (); Print (arr);

The result is:[' 3 ', ' 2 ', ' 1 ']

sort ()--Sorts the specified list (if the list appears with both letters and numbers, it throws an exception)

arr=["3","1","2","4","9","7","8","5","0"]arr.sort ();Print(arr);

The results are:[' 0 ', ' 1 ', ' 2 ', ' 3 ', ' 4 ', ' 5 ', ' 7 ', ' 8 ', ' 9 ']

The .del keyword: You can delete an element of the list specified subscript range

 arr=[ " a   ", "  b   ", "  c   ", "  d   ", "  e   ", "  f   ", "  g   " ]  del  arr[0:3  " print  (arr); 

The result is:[' d ', ' e ', ' f ', ' G ']

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The next day to learn python, energetic or very abundant, hope to continue to anger, so far away from the great god of Python!

Go on with your studies, don't blow.

Python next day-list basic features