Python basic 6-(high order, anonymous, partial) functions | Decorative Device

It's a bit more advanced here, and it's a little interesting to learn here, but I've seen the similarities with other languages.

higher-order functions are called higher-order functions by passing other functions as parameters.defAdd (x, Y, f):returnF (x) +f (Y) Add (-5, 6, ABS)# One#anonymous function Python uses lambda to create anonymous functionssum =LambdaArg1, Arg2:arg1 +Arg2sum (10, 20)# -#The reduce built-in function is a two-element operation function that uses a data collection of all data for two-dollar operation#a func () operation is performed on the 1th, 2 data of the set, and the resulting result is run with the third data in Func (), so that a result is finally obtained.#as the name implies, reduce shrinks a list to a value fromFunctoolsImportReducel= [1,2,3,4,5]Print(Reduce (LambdaX, Y:x-y, 1))#At the beginning of x, assign a value of 10, and then clickPrint(Reduce (LambdaX, Y:x-y, L, 10))#map applies to each iteration of the item returns a result the List,map function iterates through each parameter with the corresponding processing function#The essence is to change the original list into another list according to the Lambda Law.L = [1, 2, 3]new_list= List (Map (LambdaI:i+1, L))#became [2, 3, 4]L2= [4, 5, 6]new_list= List (Map (LambdaX, Y:x +y, L, L2)) #became [5, 7, 9]#filter processing of sequencesL = [100, 20, 24, 50, 110]new= List (Filter (LambdaX:x < 50, L))#[A]#@before @test in decorators and test methods @end similar to the parameters and multiple adorners#in short, you need to do something uniformly when you're dealing with a method. fromFunctoolsImportWrapsdefMakehtmltag (tag, *args, * *Kwds):defReal_decorator (FN):#fn is hello ()Css_class ="class= ' {0} '". Format (kwds["Css_class"])             if "Css_class" inchKwdsElse ""            defWrapped (*args, * *Kwds):return "<"+ tag + Css_class +">"+ FN (*args, **kwds) +"</"+tag+">"            returnWrappedreturnReal_decorator@makehtmltag (Tag="b", css_class="Bold_css") @makeHtmlTag (tag="I", css_class="Italic_css")defHello ():return "Hello World" Print(Hello ())#<b class= ' bold_css ' ><i class= ' italic_css ' >hello world</i>#here are two layers of B for the outermost layer, I for the middle tier#High efficiency recursion There's a problem here is that input 60 will exceed the integer range to give an error . fromFunctoolsImportWraps fromDatetimeImportdatetimedefMemo (FN): Cache={} Miss=object () @wraps (FN)defWrapper (*args): Result=cache.get (args, Miss)ifResult isMiss:result= FN (*args) Cache[args]=resultreturnresultreturnWrapper@memodeffib (n):ifN<2:            returnNreturnFIB (n-1) + fib (n-2) Start=DateTime.Now ()Print(FIB (40))#102334155End =DateTime.Now ()Print((End-start). microseconds)#71061deffib2 (n):ifN<2:            returnNreturnFIB2 (n-1) + FIB2 (n-2) Start1=DateTime.Now ()Print(FIB2 (40))#102334155End1 =DateTime.Now ()Print((END1-START1). microseconds)#641741      #Partial function only sets part of the parameterint'123455')#default conversion to 10 binaryint'123456', base 8)#8 binaryint'123456', base 16)#16 binary#for convenience, you don't need to enter as many binary values each time.defInt2 (x, base=2):    returnInt (x, base)#using functools.partial to create a biased functionImportFunctoolsint2= functools.partial (int, base=2)Print(Int2 ('1000000'))#Pass dictionary can default parametersKW = {'Base': 2}Print(Int ('10010', **kw))#Pass Listargs = (10, 5, 6, 7)Print(Max (*args))

Python basic 6-(high order, anonymous, partial) functions | Decorative Device