Print in one line dynamically

Question

I would like to make several statements that give standard output without seeing newlines in between statements.

Specifically, suppose I have:

for item in range(1,100):
    print item

The result is:

1
2
3
4
.
.
.

How get this to instead look like:

1 2 3 4 5 ...

Even better, is it possible to print the single number over the last number, so only one number is on the screen at a time?

Answer 1

You can add a trailing comma to your print statement to print a space instead of a newline in each iteration:

print item,

Alternatively, if you're using Python 2.6 or later, you can use the new print function, which would allow you to specify that not even a space should come at the end of each item being printed (or allow you to specify whatever end you want):

from __future__ import print_function
...
print(item, end="")

Finally, you can write directly to standard output by importing it from the sys module, which returns a file-like object:

from sys import stdout
...
stdout.write( str(item) )

Answer 2

The best way to accomplish this is to use the \r character

Just try the below code:

import time
for n in range(500):
  print(n, end='\r')
  time.sleep(0.01)
print()  # start new line so most recently printed number stays

Answer 3

In Python 3 you can do it this way:

for item in range(1,10):
    print(item, end =" ")

Outputs:

1 2 3 4 5 6 7 8 9 

Tuple: You can do the same thing with a tuple:

tup = (1,2,3,4,5)

for n in tup:
    print(n, end = " - ")

Outputs:

1 - 2 - 3 - 4 - 5 - 

Another example:

list_of_tuples = [(1,2),('A','B'), (3,4), ('Cat', 'Dog')]
for item in list_of_tuples:
    print(item)

Outputs:

(1, 2)
('A', 'B')
(3, 4)
('Cat', 'Dog')

You can even unpack your tuple like this:

list_of_tuples = [(1,2),('A','B'), (3,4), ('Cat', 'Dog')]

# Tuple unpacking so that you can deal with elements inside of the tuple individually
for (item1, item2) in list_of_tuples:
    print(item1, item2)   

Outputs:

1 2
A B
3 4
Cat Dog

another variation:

list_of_tuples = [(1,2),('A','B'), (3,4), ('Cat', 'Dog')]
for (item1, item2) in list_of_tuples:
    print(item1)
    print(item2)
    print('\n')

Outputs:

1
2


A
B


3
4


Cat
Dog

Answer 4

For Python(2.7)

 l=""                             #empty string variable
    for item in range(1,100):
        item=str(item)            #converting each element to string
        l=l+" "+item              #concating each element
        l.lstrip()                # deleting the space that was created initially 
    print l                      #prining the whole string

Python 3

 l=""
        for item in range(1,100):
            item=str(item)
            l=l+" "+item
            l.lstrip()
        print(l)

Answer 5

Use print item, to make the print statement omit the newline.

In Python 3, it's print(item, end=" ").

If you want every number to display in the same place, use for example (Python 2.7):

to = 20
digits = len(str(to - 1))
delete = "\b" * (digits + 1)
for i in range(to):
    print "{0}{1:{2}}".format(delete, i, digits),

In Python 3, it's a bit more complicated; here you need to flush sys.stdout or it won't print anything until after the loop has finished:

import sys
to = 20
digits = len(str(to - 1))
delete = "\b" * (digits)
for i in range(to):
   print("{0}{1:{2}}".format(delete, i, digits), end="")
   sys.stdout.flush()