Overwriting the printed line every print for time algorithm

Question

I am trying to write a time algorithm. However, I am having a problem successfully printing the code on the same line by overwriting the previous print

I have tried to use "\r" to print it on the same line. However, it does not work as after finishing the first minute, the seconds go like 09,19,29,39 and so on.. not sure what the problem is here.

However, if I remove the "\r", the program works fine except it prints the time in a new line every time. I want to print it in the same line.

import time
for i in range(24):
    for a in range(60):
        for s in range(60):
            print(i,":",a,":",s, end='\r')
            time.sleep(1)

I expect the output to be a just like normal time. However it isn't working the same way not sure why

I am sure this question has been asked before. Let me see... — , Apr 04 '19 at 17:04
https://stackoverflow.com/questions/5290994/remove-and-replace-printed-items — , Apr 04 '19 at 17:06
yes I looked at some similiar ones from which I found out "\r". However, it still wasn't working. Turns out there was some other mistake — Mayank agrawal, Apr 04 '19 at 17:09
Oh ok then. The code worked fine for me, But maybe some problem. No problem. — , Apr 04 '19 at 17:11
The new solution as given works fine in the terminal. Was wondering why this does not work in idle? — Mayank agrawal, Apr 04 '19 at 17:14
Have you named your file after a module?? Like have you named your file time?? — , Apr 04 '19 at 17:18
The reason why that isn't working is because the time module file is name time.py. If you name it after, the new file for the time module won't be defined. It will pass an error. To delete it, type in ```import os```, then type ```os.delete("time.py")```. This will work if it is in the same directory. — , Apr 04 '19 at 17:30
If you rename it, then it just creates a copy, not rename it. The original file is still called time.py. You have to delee it with the os module. — , Apr 04 '19 at 17:34
Actually, I did not rename it. I saved the file again with a new name. — Mayank agrawal, Apr 04 '19 at 17:46

blhsing · Accepted Answer · 2019-04-04T17:24:59.680

1

The 9 character that follows 0, 1, 2, etc. after the first minute is simply the 9 in the 59 that was printed in the last second of the first minute, since the single-digit seconds do not have enough width to overwrite the 9. You can format the output of each number with a width of 2, and since we're dealing with time here, pad the numbers with leading 0:

import time
for i in range(24):
    for a in range(60):
        for s in range(60):
            print('%02d:%02d:%02d' % (i, a, s), end='\r')
            time.sleep(1)

If you run this in IDE, it will not output anything because the output is buffered until a newline character is received. You can force-flush the output with the flush=True argument, but then the IDE will still not output anything because the \r character erases the output due to the IDE's pre-processing. You can instead flush the output first before printing \r:

import time
for i in range(24):
    for a in range(60):
        for s in range(60):
            print('%02d:%02d:%02d' % (i, a, s), end='', flush=True)
            time.sleep(1)
            print('', end='\r')

edited Apr 04 '19 at 17:24

answered Apr 04 '19 at 17:03

blhsing

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I have just recently started using visual studio code as my editor and turns out this works fine in the terminal but just wanted to ask why doesn't it work when running in idle? – Mayank agrawal Apr 04 '19 at 17:16
In IDE, the output is buffered and the IDE would only actually output the buffer to the screen when there is a newline character, and there is no newline character output from this code. – blhsing Apr 04 '19 at 17:19
I tried to run the new solution and the old solution on IDLE, but it still results in the output time printed side by side – Mayank agrawal Apr 04 '19 at 17:29
Python's IDLE does not support moving the cursor to the beginning of a line using the `\r` character at all, so it is simply not possible with IDLE. Please simply use a different IDE. – blhsing Apr 04 '19 at 17:36

Overwriting the printed line every print for time algorithm

1 Answers1