如何使输出更具可读性？

Question

我编写了以下代码，它将素数打印到所需的数字。

def prime_number(number1):
    for desired_num in range(1,int(number1)+1):
       if desired_num > 1:
          for i in range(2,desired_num):
              if (desired_num % i) == 0:
              break
          else:
              print(desired_num)
number2 = int(raw_input ("Enter any number :- "))
print "Prime numbers between 1 and", number2, "are :-"
prime_number(number2)    

我得到的输出类似于下面的，对于一个有很多数字的列表来说变得非常麻烦。

2   
3  
5  
7  

我想要的输出与下面的类似。

[2, 3, 5, 7]   

您对如何获得所需的输出有任何建议吗？

Answer 1

为了实现您的目标（有格式化的输出），您必须对您的代码进行一些更改，换句话说，使其“更 Pythonic”：

import time
from pprint import pprint, pformat
from typing import Iterable


def prime_number(number1):
    """
    generator
    :rtype: Iterable[int]
    :type number1: int
    """
    for desired_num in range(1, int(number1) + 1):
        if desired_num > 1:
            for i in range(2, desired_num):
                if (desired_num % i) == 0:
                    break
            else:
                yield desired_num


number2 = int(raw_input("Enter any number :- "))
primes = pformat(list(prime_number(number2)))
print("Prime numbers between 1 and {} are :- {}".format(number2, primes))

我在这里使用的是 管道：pformat(list(prime_number(...))) generator -> list [1, 2, 3] -> text '[1, 3, ]'。 然后我将文本和number2 放入一个格式化字符串，并发送到打印。

如果您是python 初学者并且不熟悉generators 概念，您可以重写prime_number 函数以使用简单的.append 到一个列表而不是产生它，然后返回整个列表。

Answer 2

将append 用于新列表：

import time
def prime_number(number1):
    l=[]
    for desired_num in range(1,int(number1)+1):
       if desired_num > 1:
          for i in range(2,desired_num):
              if (desired_num % i) == 0:
              break
          else:
              l.append(desired_num)
    print(l)
number2 = int(raw_input ("Enter any number :- "))
print "Prime numbers between 1 and", number2, "are :-"
start = time.time()
prime_number(number2)
print(time.time() - start)

Answer 3

如果使用数组来存储这些素数，然后打印出来会更好。

import time

def prime_number(number1):
    primes = []
    for desired_num in range(1,int(number1)+1):
       if desired_num > 1:
          for i in range(2,desired_num):
              if (desired_num % i) == 0:
                  break
          else:
              primes.append(desire_num)
    return primes

number2 = int(raw_input ("Enter any number :- "))
print "Prime numbers between 1 and", number2, "are :-"
print(prime_number(number2)) 

Answer 4

一个简单的想法是将素数列表存储在 python 内置列表中，然后以您喜欢的格式简单地打印出来！就这么简单。

def prime_number(number1):
    primes = [] # An empty list here, that will be populated with primes!
    for desired_num in range(1,int(number1)+1):
       if desired_num > 1:
          for i in range(2,desired_num):
              if (desired_num % i) == 0:
                  break
          else:
              primes.append(desired_num)
    print "[" + ",".join(map(str, primes)) + "]" 

number2 = int(raw_input ("Enter any number :- "))
print "Prime numbers between 1 and", number2, "are :-"
primes = prime_number(number2)

Answer 5

您可以采用两种方式进行打印。将其存储在列表中，然后打印或连续打印。

方法一 Use list and then print it as comma separated:

import time
def prime_number(number1):
    output_list = list()
    for desired_num in range(1,int(number1)+1):
        if desired_num > 1:
           for i in range(2,desired_num):
               if (desired_num % i) == 0:
                   break
           else:
               output_list.append(desired_num)
    return output_list
number2 = int(raw_input ("Enter any number :- "))
print "Prime numbers between 1 and", number2, "are :-"
output_list = prime_number(number2)
print (",".join(output_list))

方法2 Print the numbers in function itself serially using end:

import time
def prime_number(number1):
    for desired_num in range(1,int(number1)+1):
        if desired_num > 1:
           for i in range(2,desired_num):
               if (desired_num % i) == 0:
                   break
           else:
               print(desired_num,end = " ")
  number2 = int(raw_input ("Enter any number :- "))
  print "Prime numbers between 1 and", number2, "are :-"
  prime_number(number2)