python函数实例化

In terms of Mathematics and Computer science, currying is the approach/technique by which we can break multiple-argument function to single argument function.

从数学和计算机科学的角度来看， 柯里化是一种方法/技术，通过它我们可以将多参数功能分解为单参数功能。

Mathematical illustration: h(x)=g(f(x))

数学图示：h(x)= g(f(x))

The composition of two functions is a chaining process in which the output becomes the input for the outer function.

两个函数的组合是一个链接过程，其中输出成为外部函数的输入。

    def currying( g , f ):
def h(x):
return g(f(x))
return h

In the technical term "Currying is the process of transforming a function that takes 'n' arguments into a series of 'n' function that only takes the one argument each."

在技​​术术语中， “固化是将采用'n'个参数的函数转换为一系列只采用一个参数的'n'函数的过程。”

In problem-solving approach, currying is to be done to simplify the programming i.e. execution of the function which takes multiple arguments into the single - single argument functions.

在解决问题的方式， 钻营被做了简化这需要多个参数到单一功能的编程也就是执行-单参数的函数。

Example code 1:

示例代码1：

def f(a):
def g(b, c, d, e):
print(a, b, c, d, e)
return g #as in f it return g this is currying
f1 = f(1)
f1(2,3,4,5)

Output

输出量

1 2 3 4 5

Explanation of the above code:

上面的代码说明：

Now, f(1) returns the function g(b, c, d, e) which, for all b, c, d, and e, behaves exactly like f(1, b, c, d, e). Since g is a function, it should support currying as well.

现在， f(1)返回函数g(b，c，d，e) ，对于所有b ， c ， d和e ，其行为都与f(1，b，c，d，e)完全一样。 由于g是一个函数，因此它也应该支持curring 。

Example code 2:

示例代码2：

def f(a):
def g(b):
def h(c):
def i(d):
def j(e):
print(a, b, c, d, e)
return j  #return to function i
return i      #return to function h
return h          #return to function g
return g              #return to function f
f(1)(2)(3)(4)(5)

Output

输出量

1 2 3 4 5

Explanation of the above code:

上面的代码说明：

In the code we have, X(a,b,c,d,e) = f(g(h(i(j(a,b,c,d,e))))

在代码中， X(a，b，c，d，e)= f(g(h(i(j(a，b，c，d，e))))

Here, the concept is of nesting of one function to another and hence the result of one function get stored or recorded in another function as a chain of functions.

在此，概念是将一个功能嵌套到另一个功能，因此一个功能的结果作为功能链存储或记录在另一个功能中。

Note: Now f(a,b,c,d,e) is no more i.e. now f no more take 5 arguments.

注意：现在f(a，b，c，d，e)不再存在，即现在f不再接受5个参数。

Python example of currying function to convert INR to pounds

将INR转换为英镑的currying函数的Python示例

# program to covert the Indian Rupee to Pound
# Demonstrating  Currying of composition of function
def change(b, c):
def a(x): #by currying function
return b(c(x))
return a
def IR2USD(ammount):
return ammount*0.014  # as 1IR=0.014USD
def USD2Pound(ammount):  # Function converting USD to Pounds
return ammount * 0.77
if __name__ == '__main__':
Convert = change(IR2USD,USD2Pound )
e = Convert(565)
print("Conveted Indian Rupee to Pound:")
print('565 INDIAN RUPEES =',e,'PoundSterling')

Output

输出量

Conveted Indian Rupee to Pound:
565 INDIAN RUPEES = 6.0907 PoundSterling

翻译自: https://www.includehelp.com/python/currying-function-with-example.aspx

python函数实例化