[python3]

[Kevin Adams]

Greetings!

Please forgive me if im posting this to the wrong group.

I'm new to Python, learning Python3 from the O'rielly "Learning
Python" book. Reading
about operator overloading, specifically __getitem__. I put together
a small bit of code to
do some experimenting and threw in a timer so i can see it do its
thing. For some reason
the time.sleep(x) function doesnt work when my print function includes
"end=''".

Thanks in advance for any help.

---code---

class TestClass():
def __init__(self):
self.data = "I was far from home and the spell of the eastern
sea was upon me."

def __getitem__(self,i):
return self.data[i]

import time

if __name__ == "__main__":

me = TestClass()
for x in me:
print(x,end='') #if i remove the 'end=''' it performs as i'd
expect
time.sleep(int(2))

[Steve Holden]

Kevin Adams wrote:
> Greetings!
>
> Please forgive me if im posting this to the wrong group.
>
> I'm new to Python, learning Python3 from the O'rielly "Learning
> Python" book. Reading
> about operator overloading, specifically __getitem__. I put together
> a small bit of code to
> do some experimenting and threw in a timer so i can see it do its
> thing. For some reason
> the time.sleep(x) function doesnt work when my print function includes
> "end=''".
>
> Thanks in advance for any help.
>
>

Try the following changes:

> ---code---
>
> class TestClass():
> def __init__(self):
> self.data = "I was far from home and the spell of the eastern
> sea was upon me."
>
> def __getitem__(self,i):
> return self.data[i]
>
>
> import time

import sys

>
> if __name__ == "__main__":
>
> me = TestClass()
> for x in me:
> print(x,end='') #if i remove the 'end=''' it performs as i'd
> expect

sys.stdout.flush()

> time.sleep(int(2))
>

It may just be that the output is being held in buffers until the
program terminates. the fluch() methof pushes it straight out.

regards
Steve
--
Steve Holden +1 571 484 6266 +1 800 494 3119
See PyCon Talks from Atlanta 2010 http://pycon.blip.tv/
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[Krister Svanlund]

> --
> http://mail.python.org/mailman/listinfo/python-list
>

I'm guessing wildly here but I think you have to flush the output.
Can't remember how right now but it won't take much googling for it.

[Terry Reedy]

On 3/19/2010 1:42 PM, Kevin Adams wrote:

> Please forgive me if im posting this to the wrong group.

Just the right place. I would suggest a more informative title in the
future though. 'Problem with print and sleep.', for instance.

>
> I'm new to Python, learning Python3 from the O'rielly "Learning
> Python" book. Reading
> about operator overloading, specifically __getitem__. I put together
> a small bit of code to
> do some experimenting and threw in a timer so i can see it do its
> thing.

Good idea. Welcome to Python.

> For some reason
> the time.sleep(x) function doesnt work when my print function includes
> "end=''".

I cut your code, pasted it into IDLE edit window, and made two minor
modifications. For me (3.1, winxp) it works perfectly either way --
chars print at 1 sec intervals either vertically or horizonatally. So I
am not sure what you are claiming.

>
> Thanks in advance for any help.
>
>
> ---code---
>
> class TestClass():
> def __init__(self):
> self.data = "I was far from home and the spell of the eastern
> sea was upon me."

I shortened string

>
> def __getitem__(self,i):
> return self.data[i]
>
> import time
>
> if __name__ == "__main__":
>
> me = TestClass()
> for x in me:
> print(x,end='') #if i remove the 'end=''' it performs as i'd
> expect
> time.sleep(int(2))

int(2) == 2, so delete irrelevant call, and 1 sec is enough

Terry Jan Reedy

[Kevin Adams]

Thanks to all!!!

It did indeed turn out to be a need to flush the stdout.

K

ps. sorry for the brief subject, i wasnt finish and hit send before
comming back to it.

[Terry Reedy]

On 3/19/2010 2:17 PM, Steve Holden wrote:

> Kevin Adams wrote:
>> Greetings!
>>
>> Please forgive me if im posting this to the wrong group.
>>
>> I'm new to Python, learning Python3 from the O'rielly "Learning
>> Python" book. Reading
>> about operator overloading, specifically __getitem__. I put together
>> a small bit of code to
>> do some experimenting and threw in a timer so i can see it do its
>> thing. For some reason
>> the time.sleep(x) function doesnt work when my print function includes
>> "end=''".
>>
>> Thanks in advance for any help.
>>
>>

> Try the following changes:

>
>> ---code---
>>
>> class TestClass():
>> def __init__(self):
>> self.data = "I was far from home and the spell of the eastern
>> sea was upon me."
>>
>> def __getitem__(self,i):
>> return self.data[i]
>>
>>
>> import time
>

> import sys

>>
>> if __name__ == "__main__":
>>
>> me = TestClass()
>> for x in me:
>> print(x,end='') #if i remove the 'end=''' it performs as i'd
>> expect

> sys.stdout.flush()
>
>> time.sleep(int(2))
>
> It may just be that the output is being held in buffers until the
> program terminates. the fluch() methof pushes it straight out.

The IDLE Shell window must get print output back from the pythonw
process without buffering. When I cut and pasted from IDLE editor to
standard interpreter window, output was bunched after several seconds.
OP should have started with short string and minimal delay so output
would not take a whole minute. Flushing fixed problem in standard
interpreter. I will have to remember that testing partial line output in
IDLE does not show how it will act elsewhere.

Kevin: when reporting a problem, be more specific as to what 'does not
work' means.

Terry Jan Reedy

[Kevin Adams]

On Mar 19, 3:02 pm, Terry Reedy <tjre...@udel.edu> wrote:

Terry: Will definately try to be more informative next time. Thanks
again.

K