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Why prefer two's complement over sign-and-magnitude for signed numbers?
...o add them.
Two's complement addition is very simple. You add numbers normally and any carry bit at the end is discarded. So they're added as follows:
0010
+ 1111
=10001
= 0001 (discard the carry)
0001 is 1, which is the expected result of "2+(-1)".
But in your "intuitive" method, adding is m...
Why is “if not someobj:” better than “if someobj == None:” in Python?
...a __nonzero__ special method (as do numeric built-ins, int and float), it calls this method. It must either return a bool value which is then directly used, or an int value that is considered False if equal to zero.
Otherwise, if the object has a __len__ special method (as do container built-ins, li...
unique object identifier in javascript
...niqueId());
Take care to make sure that whatever member you use to internally store the unique ID doesn't collide with another automatically created member name.
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jsonify a SQLAlchemy result set in Flask [duplicate]
...
It seems that you actually haven't executed your query. Try following:
return jsonify(json_list = qryresult.all())
[Edit]: Problem with jsonify is, that usually the objects cannot be jsonified automatically. Even Python's datetime fails ;)
Wha...
how to delete all cookies of my website in php
I'm wondering if I can delete all my website's cookies when a user click on logout, because I used this as function to delete cookies but it isn't work properly:
...
method of iterating over sqlalchemy model's defined columns?
...l exclude SA magic attributes, but will not exclude the relations. So basically it might load the dependencies, parents, children etc, which is definitely not desirable.
But it is actually much easier because if you inherit from Base, you have a __table__ attribute, so that you can do:
for c in Jo...
“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... can be used to detect if a variable has been already initialized. Additionally and more ideal is the solution of empty() since it does not generate a warning or error message if the variable is not initialized.
From PHP documentation:
No warning is generated if the variable does not exist. T...
Why is using 'eval' a bad practice?
...d eval have nothing to do with each other. An application that's fundamentally mis-designed is fundamentally mis-designed. eval is no more the root cause of bad design than division by zero or attempting to import a module which is known not to exist. eval isn't insecure. Applications are insecu...
Best way to structure a tkinter application? [closed]
The following is the overall structure of my typical python tkinter program.
7 Answers
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Get class that defined method
...ited Jun 20 '14 at 19:44
Aaron Hall♦
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answered Jun 7 '09 at 2:23
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