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Reload django object from database
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Not sure what "All non-deferred fields are updated "mentioned in the docs means?
– Yunti
Nov 13 '15 at 18:15
1
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Removing duplicates from a list of lists
... much easier that it offers good returns on efforts. But sometimes (essentially for "tragically crucial bottlenecks" in deep inner loops of code that's pushing the boundaries of performance limits) one may need to go into much more detail, providing probability distributions, deciding which performa...
Python string class like StringBuilder in C#?
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There is no one-to-one correlation. For a really good article please see Efficient String Concatenation in Python:
Building long strings in the Python
progamming language can sometimes
result in very slow running code. In
this article I investigate the
comp...
How do I detect unsigned integer multiply overflow?
I was writing a program in C++ to find all solutions of a b = c , where a , b and c together use all the digits 0-9 exactly once. The program looped over values of a and b , and it ran a digit-counting routine each time on a , b and ab to check if the digits condition was satisfied.
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How do I analyze a program's core dump file with GDB when it has command-line parameters?
...xt_ptr = "string in text segment";
(void)argv;
mmap_ptr = (char *)malloc(sizeof(data_ptr) + 1);
strcpy(mmap_ptr, data_ptr);
mmap_ptr[10] = 'm';
mmap_ptr[11] = 'm';
mmap_ptr[12] = 'a';
mmap_ptr[13] = 'p';
printf("text addr: %p\n", text_ptr);
printf("data addr: %p\n...
How does functools partial do what it does?
...xtend(extra_args)
return func(*args)
return wrapper
So, by calling partial(sum2, 4) you create a new function (a callable, to be precise) that behaves like sum2, but has one positional argument less. That missing argument is always substituted by 4, so that partial(sum2, 4)(2) == sum2...
java get file size efficiently
...97.044
URL sum: 95534, per Iteration: 382.136
File must be caching the calls to the filesystem, while channels and URL have some overhead.
Code:
import java.io.*;
import java.net.*;
import java.util.*;
public enum FileSizeBench {
LENGTH {
@Override
public long getResult() ...
Python Dictionary Comprehension
...>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
>>> d = {n: True for n in range(5)}
>>> print d
{0: True, 1: True, 2: True, 3: True, 4: True}
What you seem to be asking for is a way to set multiple keys at once on an existing dictionary. ...
How to get the request parameters in Symfony 2?
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The naming is not all that intuitive:
use Symfony\Component\HttpFoundation\Request;
public function updateAction(Request $request)
{
// $_GET parameters
$request->query->get('name');
// $_POST parameters
$request->r...
How to create a video from images with FFmpeg?
...pix_fmt yuv420p out.ogg
Your images should of course be sorted alphabetically, typically as:
0001-first-thing.jpg
0002-second-thing.jpg
0003-and-third.jpg
and so on.
I would also first ensure that all images to be used have the same aspect ratio, possibly by cropping them with imagemagick or n...