How to remove a whitespace from a string

Question

What I want my code to do is that eventually the "-" will collide with the "0". But right now all it does is keep chasing the "0" and never touch it.

import time
global gunshot, gun
gun = 0
gunshot = "-           0"

while True:
    global gunshot
    gunshot = " " + gunshot
    gunshot.replace(' 0', '0')
    print ('\r {0}'.format(gunshot)),
    if gunshot.find("-0") == 1:
        gunshot = "-"
    time.sleep(.1)

That is want I want:

     -     0
      -    0
       -   0

This is what it is doing

     -     0
     -     0
     -     0

You are replacing the space but not assigning the result into gunshot. Gunshot = gunshot.replace() — Vivek Kumar
– Vivek Kumar, Commented Jan 31, 2017 at 3:08
You don't need to declare global variables like that: global gunshot, gun. That makes only sense if you are in a function and want to modify a gunshot and gun variable (which are outside of your function). — MSeifert
– MSeifert, Commented Jan 31, 2017 at 3:23

George John · Accepted Answer · 2017-01-31 03:17:10Z

1

replace returns a new string, it does not change the variable inplace.

gunshot = gunshot.replace(' 0', '0')

This will fix your immediate problem, but you should consider using @MSeiferts code because it is much better.

edited Jan 31, 2017 at 3:17

answered Jan 31, 2017 at 3:09

George John

1181 silver badge7 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Cube Over a year ago

how do i change variable inplace?

MSeifert Over a year ago

You can't change a string in-place in Python but you can reassign the variable name.

MSeifert · Accepted Answer · 2017-01-31 03:10:22Z

1

You could use the str.format and str.rjust function here:

bullet = '-'
target = 'O'

distance = 3
field = 10

while distance >= 0:
    print('{}{}{}'.format(bullet, ' '*distance, target).rjust(field))
    distance -= 1

which prints:

answered Jan 31, 2017 at 3:10

MSeifert

154k41 gold badges356 silver badges377 bronze badges

Comments

Aaron Hampton · Accepted Answer · 2017-01-31 03:36:24Z

0

You could also use a deque and just rotate the values:

from collections import deque


def gunshot_path(distance):
    return deque(['-'] + ([''] * (distance - 1)))


def print_gunshot_path(distance, target="0"):
    path = gunshot_path(distance)
    for i in range(distance):
        print(" ".join(path) + target)
        path.rotate()


print_gunshot_path(5)
print_gunshot_path(10, target='X')

Which prints:

-    0
 -   0
  -  0
   - 0
    -0
-         X
 -        X
  -       X
   -      X
    -     X
     -    X
      -   X
       -  X
        - X
         -X

answered Jan 31, 2017 at 3:36

Aaron Hampton

8948 silver badges26 bronze badges

Collectives™ on Stack Overflow

How to remove a whitespace from a string

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related