Python学习——列表
【1】#列表的表示:
列表中用方括号[ ]表示,元素之间用逗号,隔开。
>>>property=['name','gender','weight','height']
>>>property
['name','gender', 'weight', 'height']
【2】#元素索引:
>>>property[0]
'name'
【3】#列表中第一个元素标号,依次累加;此外,最后可以通过-1索引最后一个元素,方向依次累减:
例1:
>>>property=['name','gender','weight','height']
>>>print(property[0]+'\n'+property[1]+'\n'+property[2]+'\n'+property[3])
name
gender
weight
height
例2:
>>>property=['name','gender','weight','height']
>>>print(property[-1]+'\n'+property[-2]+'\n'+property[-3]+'\n'+property[-4])
height
weight
gender
name
【4】#修改列表元素,修改列表下表并赋值:
>>>property=['name','gender','weight','height']
>>>print(property)
['name','gender', 'weight', 'height']
>>>property[1]='boy'
>>>print(property)
['name','boy', 'weight', 'height']
【5】#在列表末尾添加新元素append(‘元素’):
例1:
>>>property=['name','gender','weight','height']
>>>print(property)
['name','gender', 'weight', 'height']
>>>property.append('new_factor')
>>>print(property)
['name','gender', 'weight', 'height', 'new_factor']
例2:
>>>property_empty=[]
>>>property_empty.append('one')
>>>property_empty.append('two')
>>>property_empty.append('three')
>>>print(property_empty)
['one','two', 'three']
【6】#在列表中插入元素insert(位置,’新元素’):
>>>property=['name','gender','weight','height']
>>>print(property)
['name','gender', 'weight', 'height']
>>>property.insert(1,'new_factor')
>>>print(property)
['name','new_factor', 'gender', 'weight', 'height']
【7】#列表中删除元素del列表[位置]
>>>property=['name','gender','weight','height']
>>>print(property)
['name','gender', 'weight', 'height']
>>>del property[0]
>>>print(property)
['gender','weight', 'height']
【8】#使用pop(位置),删除元素(即:从列表中弹出元素)
>>>property=['name','gender','weight','height']
>>>print(property)
['name', 'gender','weight', 'height']
>>>tan_chu=property.pop(2)
>>>print(property)
['name','gender', 'height']
>>>print(tan_chu)
Weight
【9】#使用remove(‘元素’),删除列表中指定的元素:
例1:
>>>property=['name','gender','weight','height']
>>>remove_factor=property[1]
>>>property.remove(remove_factor)
>>>print(property)
['name','weight', 'height']
>>>print(remove_factor)
Gender
例2:
>>>property=['name','gender','weight','height']
>>>remove_factor='gender'
>>>property.remove(remove_factor)
>>>print(property)
['name', 'weight','height']
【10】#sort()函数,对列表实现永久排序:
例1,正向排序.sort():
>>>ex_list=['bill','alice','calen','eva','demen']
>>>print(ex_list)
['bill','alice', 'calen', 'eva', 'demen']
>>>ex_list.sort()
>>>print(ex_list)
['alice','bill', 'calen', 'demen', 'eva']
例2,反向排序.sort(reverse=True)、(注:True首字母注意大小写):
>>>ex_list=['bill','alice','calen','eva','demen']
>>>print(ex_list)
['bill','alice', 'calen', 'eva', 'demen']
>>>ex_list.sort(reverse=True)
>>>print(ex_list)
['eva','demen', 'calen', 'bill', 'alice']
【11】#sorted()函数,对列表实现临时排序:
例1:
>>>ex_list=['bill','alice','calen','eva','demen']
>>>temporary=sorted(ex_list)
>>>print(temporary)
['alice','bill', 'calen', 'demen', 'eva']
>>>print(sorted(ex_list))
['alice','bill', 'calen', 'demen', 'eva']
>>>print(ex_list)
['bill','alice', 'calen', 'eva', 'demen']
例2,正反序:
>>>ex_list=['bill','alice','calen','eva','demen']
>>>temporary_positive=sorted(ex_list)
>>>temporary_passive=sorted(ex_list,reverse=True)
>>>print(ex_list,'\n',temporary,'\n',temporary_positive)
['bill','alice', 'calen', 'eva', 'demen']
['eva', 'demen', 'calen', 'bill', 'alice']
['alice', 'bill', 'calen', 'demen', 'eva']
【12】#reverse()函数,颠倒列表元素顺序:
>>>ex_list=['bill','alice','calen','eva','demen']
>>>print(ex_list)
['bill','alice', 'calen', 'eva', 'demen']
>>>ex_list.reverse()
>>>copy_1=ex_list
>>>print('\n',ex_list,'\n',copy_1)
['demen', 'eva', 'calen', 'alice', 'bill']
['demen', 'eva', 'calen', 'alice', 'bill']
【13】#len(列表),确定列表长度:
>>>ex_list=['bill','alice','calen','eva','demen']
>>>len_list=len(ex_list)
>>>print('\t',len_list)
5
领取专属 10元无门槛券
私享最新 技术干货