[Tutor] pickle problems

[Richard D. Moores]

On Sat, Aug 11, 2012 at 9:51 PM, eryksun <eryksun at gmail.com> wrote:
> On Sat, Aug 11, 2012 at 11:19 PM, Richard D. Moores <rdmoores at gmail.com> wrote:
>>
>>> To clarify, you can store multiple pickles in a file, but each needs
>>> its own load. So you'd have to maintain a session dictionary for the
>>> factors of new integers. Then append the pickled session to the file
>>> when the user quits. When the program starts you'd have to loop
>>> through the file to update D with each pickled session.
>>
>> Isn't that essentially what my script does?
>
> On line 69 your script (http://pastebin.com/SNwKRuSK) appends the
> current D to the end. So only the last pickle appended would be
> complete. My first response was for you to switch to 'wb' mode to
> truncate the file and only save the latest complete session.
>
> Then it occurred to me that you actually wanted to grow the pickle the
> file. I proposed the above solution to append the new factorizations
> per session. Then at the start load the pickled sessions in a loop,
> updating D with each loaded dictionary. For example:

OK, thanks for the code, which I will duly study. However, I just
pasted my new version, pickle_attempt_for_web2.py at
<http://pastebin.com/EZUKjPSk>. I've tested it and tested it, and it
does exactly what I wanted (thanks to you!). Yes, you're correct, I
want to grow the pickle file, the dictionary. The new version puts
every new item into it -- nothing gets lost.

One caveat is that I have yet to fix the problem with lines 75-78.

One thing I'd like to implement is a monitor of the time
factorsOfInteger(n) takes to process some of the 18-digit ints (line
153). Most are processed within a second or two, but some can take
several minutes. I'd like to limit the time to 15 or 20 seconds, but
is there a way to do this? Just a wild guess, but is this where
threading would be useful?

Dick