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Default filter in Django admin
...
In order to achieve this and have a usable 'All' link in your sidebar (ie one that shows all rather than showing pending), you'd need to create a custom list filter, inheriting from django.contrib.admin.filters.SimpleListFilter ...
How to normalize an array in NumPy?
...iving optimal performance.
import numpy as np
def normalized(a, axis=-1, order=2):
l2 = np.atleast_1d(np.linalg.norm(a, order, axis))
l2[l2==0] = 1
return a / np.expand_dims(l2, axis)
A = np.random.randn(3,3,3)
print(normalized(A,0))
print(normalized(A,1))
print(normalized(A,2))
prin...
C++ Redefinition Header Files (winsock2.h)
...t;winsock2.h> #include <ws2tcpip.h> #include <windows.h> in order and was getting winsock2,h file not found. Included #define _WINSOCKAPI_ above all 3 includes still the same error
– Ava
Mar 8 '12 at 19:06
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Difference between Repository and Service Layer?
...ce layer This part operates on view models.
EDIT:
Example of flow for /Orders/ByClient/5 (we want to see order for specific client):
public class OrderController
{
private IOrderService _orderService;
public OrderController(IOrderService orderService)
{
_orderService = orde...
Get first n characters of a string
...}
Update 3:
It's been a while since I wrote this answer and I don't actually use this code any more. I prefer this function which prevents breaking the string in the middle of a word using the wordwrap function:
function truncate($string,$length=100,$append="&hellip;") {
$string = trim($st...
Precedence and bitmask operations
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You are actually doing this:
var_dump(0b10 & (0b01 == 0));
var_dump(0b10 & (0b01 != 0));
Try:
var_dump((0b10 & 0b01) == 0);
var_dump((0b10 & 0b01) != 0);
...
What's the difference between SortedList and SortedDictionary?
...--------+---------+
* Insertion is O(1) for data that are already in sort order, so that each
element is added to the end of the list (assuming no resize is required).
From an implementation perspective:
+------------+---------------+----------+------------+------------+------------------+
| ...
Fastest way to get the first object from a queryset in django?
...
also, first() and last() enforce an ORDER BY clause on a query. It will make the results deterministic but will most probably slow the query down.
– Phil Krylov
Jun 27 '17 at 19:24
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Why isn't sizeof for a struct equal to the sum of sizeof of each member?
... @YoYoYonnY that's not possible. The compiler is not allowed to reorder struct members although gcc has an experimental option to do that
– phuclv
Mar 2 '17 at 2:57
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What is a mixin, and why are they useful?
...
This particular example could have been achieved via the functools.total_ordering() decorator, but the game here was to reinvent the wheel:
import functools
@functools.total_ordering
class Integer(object):
def __init__(self, i):
self.i = i
def __le__(self, other):
return s...