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What is “2's Complement”?
... 22 + 1 × 21 + 1 × 20and if you work it out, that turns out to equal 15 (base 10). That's because it is 8+4+2+1 = 15.
This is all well and good for positive numbers. It even works for negative numbers if you're willing to just stick a minus sign in front of them, as humans do with decimal nu...
Comparing object properties in c# [closed]
...oblems with overriding .Equals() because i'm trying to implement this on a base class that gets inherited... because I don't know the keys for the class this'll be run against, i can't implement a decent override for GetHasCode() (req'd when you override Equals()).
– nailitdown...
Resumable downloads when using PHP to send the file?
...d in comments below have been incorporated.
A tested, working solution (based heavily on Theo's answer above) which deals with resumable downloads, in a set of a few standalone tools. This code requires PHP 5.4 or later.
This solution can still only cope with one range per request, but under any...
Efficiently updating database using SQLAlchemy ORM
...on. Basically, from one side, ORM data modifications will only hit the database when you flush the changes from your session. From the other side, SQL data manipulation statements don't affect the objects that are in your session.
So if you say
for c in session.query(Stuff).all():
c.foo = c.fo...
How to use single storyboard uiviewcontroller for multiple subclass
...e the UI elements in a UIView - in a xib file and instantiate it from your base class and add it as a sub view in the main view, typically self.view. Then you would simply use the storyboard layout with basically blank view controllers holding their place in the storyboard but with the correct view ...
How can I handle time zones in my webapp?
...iguously used. This looks like a reference: en.wikipedia.org/wiki/Tz_database From what I can tell a "timezone" is "Area/Location", e.g. "America/New_York". That appears to be geographic which is great because for instance America/Los_Angeles means BOTH PST and PDT depending on whether the globe...
How to avoid explicit 'self' in Python?
...
One extreme example: you can write a class without any knowledge of what base classes it might have, and always know whether you are accessing a member or not:
class A(some_function()):
def f(self):
self.member = 42
self.method()
That's the complete code! (some_function returns the t...
(![]+[])[+[]]… Explain why this works
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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How to filter array in subdocument with MongoDB [duplicate]
...
Use $filter aggregation
Selects a subset of the array to return based on the specified
condition. Returns an array with only those elements that match the
condition. The returned elements are in the original order.
db.test.aggregate([
{$match: {"list.a": {$gt:3}}}, // <-- mat...
What are “named tuples” in Python?
...ctions, only fields with them. You can even use your named tuple types as base classes:
class Point(namedtuple('Point', 'x y')):
[...]
However, as with tuples, attributes in named tuples are immutable:
>>> Point = namedtuple('Point', 'x y')
>>> pt1 = Point(1.0, 5.0)
>&g...