如何打印没有换行或空间？

Question

The question is in the title.

I'd like to do it in python. What I'd like to do in this example in c:

#include <stdio.h>

int main() {
    int i;
    for (i=0; i<10; i++) printf(".");
    return 0;
}

Output:

..........

In Python:

>>> for i in xrange(0,10): print '.'
.
.
.
.
.
.
.
.
.
.
>>> for i in xrange(0,10): print '.',
. . . . . . . . . .

In Python print will add a \n or a space, how can I avoid that? Now, it's just an example. Don't tell me I can first build a string then print it. I'd like to know how to "append" strings to stdout.

转载于:https://stackoverflow.com/questions/493386/how-to-print-without-newline-or-space

Answer 1

General way

import sys
sys.stdout.write('.')

You may also need to call

sys.stdout.flush()

to ensure stdout is flushed immediately.

Python 2.6+

From Python 2.6 you can import the print function from Python 3:

from __future__ import print_function

This allows you to use the Python 3 solution below.

Python 3

In Python 3, the print statement has been changed into a function. In Python 3, you can instead do:

print('.', end='')

This also works in Python 2, provided that you've used from __future__ import print_function.

If you are having trouble with buffering, you can flush the output by adding flush=True keyword argument:

print('.', end='', flush=True)

However, note that the flush keyword is not available in the version of the print function imported from __future__ in Python 2; it only works in Python 3, more specifically 3.3 and later. In earlier versions you'll still need to flush manually with a call to sys.stdout.flush().