如何在 Python 中制作一长串数字

Question

My question is about a simple program I wrote it in python. I like to create a 'note' file included a list from: "point 100,000" to "point 999999" placed in each lines separately:

point 100,000

point 100,001

...

point 999,999

I wrote this code:

new = ''
for m in range(100000,999999):
    new = new + 'point ' + str(m) + '\n'
fw = open('list.txt', 'w')
fw.write(new)

It works, but unfortunately it takes about 45 minutes for running. please help me to correct this code.

Answer 1

Avoid the unnecessary string concatenation, write to the file directly instead:

with open('list.txt', 'w') as fw:
    for m in range(100000,999999):
        fw.write('point ' + str(m) + '\n')

Answer 2

Use xrange for better performance.

with open('list.txt', 'w') as fw:
    for m in xrange(100000,999999):
        fw.write('point {}\n'.format(str(m))

Answer 3

Try the following:

with open('lists.txt', 'w') as fw:
    for m in range(100000,999999):
        fw.write('point ' + str(m) + '\n')

Then, you do not need to store all the content in a string before writing it to the file.