4.1.5.2 高阶函数电子课件幻灯片

高阶函数高阶函数高阶函数以函数作为输入输出的函数函数的参数是函数函数的返回值是函数满足一个即为高阶函数高阶函数defaction(name):print(name+"eat!")

defdo(animal,func):func(animal)

do("pig",action)pigeat!defdo(animal,func):func(animal)do("pig",lambdaname:print(name+"eat!"))pigeat!Python自带的高阶函数Python自带的高阶函数sortedmapreducefiltersorted函数sorted(iterable,key=None,reverse=False)stu_lst=[("Tom",20),("Jack",18),("Rose",18),("Lily",21)]new_lst=sorted(stu_lst)print(new_lst)[('Jack',18),('Lily',21),('Rose',18),('Tom',20)]stu_lst=[("Tom",20),("Jack",18),("Rose",18),("Lily",21)]new_lst=sorted(stu_lst,key=lambdaitem:item[1])print(new_lst)[('Jack',18),('Rose',18),('Tom',20),('Lily',21)]map函数map(function,sequence)defsquare(n):returnn**2num_list=[1,2,3,4,5]new_list=list(map(square,num_list))print(new_list)[1,4,9,16,25]map函数map(function,sequence)namelst=['adam','LISA','toM']m_namelst=map(lambdas:s.upper(),namelst)new_namelst=list(m_namelst)print(new_namelst)['ADAM','LISA','TOM']reduce函数reduce(function,sequence[,initial])fromfunctoolsimportreduceresult=reduce(lambdax,y:x+y,[1,2,3,4,5])print(result)15fromfunctoolsimportreduceresult=reduce(lambdax,y:x+y,[1,2,3,4,5],19)print(result)34filter函数filter(function,sequence)defis_even(n):returnn%2==0num_list=[1,2,3,4,5,6,7,8,9,10]new_list=list(filter(is_even,num_list))print(new_list)[2,4,6,8,10]应用案例stu_lst=["04161589李雨昕男","04161588刘泳锋男","04161578付懿杨男","04161576李立敏男","04161602吴谨男","04161579陈雨菲女","04161581刘凡钊女","04161585舒千茹女","04161582马思琦女"]要求：按照学号对学生进行分组。如果学号除以3的余数是1，则分到一组；如果学号除以3的余数是2，则将学生分到二组；如果学号能被3整除，则将学生分到三组。应用案例defsplit_group(grouped,value):group_num=int(value.split()[0])%3ifgroup_num==1:grouped['一组'].append(value.split()[1:])elifgroup_num==2:grouped['二组'].append(value.split()[1:])elifgroup_num==0:grouped['三组'].append(value.split()[1:])returngroupedfromfunctoolsimportreducestu_lst=["04161589李雨昕男","04161588刘泳锋男","04161578付懿杨男","04161576李立敏男","04161602吴谨男","04161579陈雨菲女","04161581刘凡钊女","04161585舒千茹女","04161582马思琦女"]grouped_stu_dic=re