A list of Python learning

1.List function

The list function can create character lists through strings, as shown here:

>>> list (' Hello ') [' H ', ' e ', ' l ', ' l ', ' O ']

The list function can be used for all types of sequences, not limited to strings.

2. Basic operation of the list2.1 Element Assignment

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

2.2 Deleting an element

>>> x[1, 4, 3]>>> del x[1]>>> x[1, 3]

2.3 Shard Assignment

>>> name=list (' Perl ') >>> name[' P ', ' e ', ' r ', ' L ']>>> name[2:][' r ', ' L ']>>> name[2: ]=list (' ar ') >>> name[' P ', ' e ', ' a ', ' R ']

>>> name[' P ', ' e ', ' a ', ' R ']>>> name[2:]=list (' Nsil ') >>> name[' P ', ' e ', ' n ', ' s ', ' I ', ' l ']> ;>> name[1:1]=[1,2,3]>>> name[' P ', 1, 2, 3, ' e ', ' n ', ' s ', ' I ', ' l ']>>> name[1:1]=list (' 123 ') > >> name[' P ', ' 1 ', ' 2 ', ' 3 ', 1, 2, 3, ' e ', ' n ', ' s ', ' I ', ' l ']>>> name[1:4]=[]>>> name[' P ', 1, 2, 3 , ' e ', ' n ', ' s ', ' I ', ' l ']

2.3append method

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

2.4count method

>>> [' sfdf ', ' sfdf ', ' SD ', ' SD '].count (' SD ') 2>>> x=[[1,2],1,1,[2,1,[1,2]]]>>> x.count (1) 2

2.5extend Method

>>> a=[1,2,3]>>> b=[4,5,6]>>> a.extend (b) >>> a[1, 2, 3, 4, 5, 6]>>> b[4, 5, 6 ]>>> a+b[1, 2, 3, 4, 5, 6, 4, 5, 6]>>> a[1, 2, 3, 4, 5, 6]>>> a=a+b>>> a[1, 2, 3, 4, 5 , 6, 4, 5, 6]

2.6 Index Method

>>> knights=[' we ', ' is ', ' the ', ' knights ', ' who ', ' say ', ' ni ']>>> knights.index (' Who ') 4>>> Knights[4] ' Who '

2.7 Insert Method

>>> numbers=[1,2,3,4]>>> numbers.insert (0, ' AA ') >>> numbers[' AA ', 1, 2, 3, 4]

2.8pop method

>>> x=[1,2,3]>>> x.pop () 3>>> x[1, 2]>>> x.pop (0) 1>>> x[2]>>> x= [1,2,3]>>> X.append (X.pop ()) >>> x[1, 2, 3]>>> x.pop (0) 1>>> x.append (3) >> > x[2, 3, 3]

2.9remove method

>>> x=[' to ', ' being ', ' or ', ' not ', ' to ', ' being ']>>> x.remove (' be ') >>> x[' to ', ' or ', ' no ', ' to ', ' being ' ‘]

2.10 Reverse Method

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

2.11 Sort Method

>>> x=[2,1,4,3,2,5]>>> x.sort () >>> x[1, 2, 2, 3, 4, 5]>>> x=[2,1,4,3,2,5]>> > y=x[:]>>> y.sort () >>> x[2, 1, 4, 3, 2, 5]>>> y[1, 2, 2, 3, 4, 5]>>> x=[4,6,2,1,7, 9]>>> y=sorted (x) >>> x[4, 6, 2, 1, 7, 9]>>> y[1, 2, 4, 6, 7, 9]

>>> x=[' qq ', ' dfsfd ', ' ssfd ', ' sdfdfffff ']>>> x.sort (key=len) >>> x[' qq ', ' ssfd ', ' dfsfd ', ' Sdfdfffff ']>>> x=[4,6,2,1,7,9]>>> x.sort (reverse=true) >>> x[9, 7, 6, 4, 2, 1]

all the attention points in the code, carefully experience the practice once again, Python's list operation is very powerful.

A list of Python learning