Comparison of Python function and Ruby related technologies

There are a lot of interesting things in the Python function. Next we will take a detailed look at the technical comparison between the Python function and Ruby. Next, let's take a look at how to apply it. I hope you will have some gains.

What is the use of Python functional programming? I think the practical advantage is that we can better describe the problem, rather than describe the operation steps to solve the problem. Let's look at a specific example:

Problem: A list. For each element, the square is removed from the list if the remainder of the square number is 1.

See the solution:

1. Traditional procedural (Python functional)

 
 

  
  
>>> s = [1,2,3]  
  
  
>>> d = []  
  
  
>>> for i in s:  
  
  
if i * i % 3 != 1:  
  
  
d.append(i * i)  
  
  
>>> d  
  
  
[9]  
  
  
>>> 
 
 

2. Traditional functional formula (Lisp)

 
 

  
  
(remove-if (lambda (n) (= (mod n 3) 1))  
  
  
(mapcar (lambda (n) (* n n))  
  
  
'(1 2 3))) 
 
 

It can be seen that the functional program corresponds to the two steps we mentioned, which are implemented by mapcar and remove-if respectively. But the Lisp program is really not very easy to read. We use python and ruby to improve it:

3. Python function:

 
 

  
  
>>> filter(lambda n: n % 3 != 1, map(lambda n:n*n, [1,2,3]))  
  
  
[9] 
 
 

4. Ruby function:

 
 

  
  
[1,2,3].map {|n| n * n}.reject{|n| n % 3 == 1}  
  
  
=> [9] 
 
 

After comparison, ruby is the most concise and most natural to the Problem description. The above is an introduction to the Python function.