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Django ManyToMany filter()
...The double underscore (__) syntax is used all over the place when working with querysets.
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Append an object to a list in R in amortized constant time, O(1)?
If I have some R list mylist , you can append an item obj to it like so:
17 Answers
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lodash multi-column sortBy descending
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edited May 21 '17 at 21:15
answered Mar 16 '15 at 17:16
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What's the difference between django OneToOneField and ForeignKey?
...d(SomeModel) and ForeignKey(SomeModel, unique=True). As stated in The Definitive Guide to Django:
OneToOneField
A one-to-one relationship. Conceptually, this is similar to a ForeignKey with unique=True, but the "reverse" side of the relation will directly return a single object.
In contra...
Rounding up to next power of 2
I want to write a function that returns the nearest next power of 2 number. For example if my input is 789, the output should be 1024. Is there any way of achieving this without using any loops but just using some bitwise operators?
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Django select only rows with duplicate field values
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Try:
from django.db.models import Count
Literal.objects.values('name')
.annotate(Count('id'))
.order_by()
.filter(id__count__gt=1)
This is as close as you can get with Django. The problem is that this will return a Val...
Why is require_once so bad to use?
...luded/required. Every *_once call means checking that log. So there's definitely some extra work being done there but enough to detriment the speed of the whole app?
... I really doubt it... Not unless you're on really old hardware or doing it a lot.
If you are doing thousands of *_once, you coul...
Add spaces before Capital Letters
Given the string "ThisStringHasNoSpacesButItDoesHaveCapitals" what is the best way to add spaces before the capital letters. So the end string would be "This String Has No Spaces But It Does Have Capitals"
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std::enable_if to conditionally compile a member function
...erstand how to use std::enable_if . After I read this answer , I thought it shouldn't be too hard to come up with a simple example. I want to use std::enable_if to choose between two member-functions and allow only one of them to be used.
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Creating Threads in python
...10, ))
thread.start()
thread.join()
print("thread finished...exiting")
Here I show how to use the threading module to create a thread which invokes a normal function as its target. You can see how I can pass whatever arguments I need to it in the thread constructor.
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