将随机数写入Python文件并使用换行符进行连接

Question

This program generates a user defined amount of random numbers and then writes to a file. The program works fine as written, but i want the text file use \\n to concatenate. What am I doing wrong?

#This program writes user defined #random numbers to a file

import random

randfile = open("Randomnm.txt", "w" )

for i in range(int(input('How many to generate?: '))):
    line = str(random.randint(1, 100))
    randfile.write(line)
    print(line)

randfile.close()

Answer 1

Add "\\n":

import random

randfile = open("Randomnm.txt", "w" )

for i in range(int(input('How many to generate?: '))):
    line = str(random.randint(1, 100)) + "\n"
    randfile.write(line)
    print(line)

randfile.close()

Answer 2

file.write() simply writes text to a file. It does not concatenate or append anything, so you need to append a \\n yourself.

(Note that the type would be called _io.TextIOWrapper in Python 3)

To do this, simply replace

line = str(random.randint(1, 100))

with

line = str(random.randint(1, 100))+"\n"

This will append a newline to every random number.

Answer 3

You could also make use of Python 3's print function's file keyword argument:

import random

with open("Randomnm.txt", "w") as handle:
    for i in range(int(input('How many to generate?: '))):
        n = random.randint(1, 100)

        print(n, file=handle)
        print(n)

# File is automatically closed when you exit the `with` block