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Select mySQL based only on month and year
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SELECT * FROM projects WHERE YEAR(Date) = 2011 AND MONTH(Date) = 5
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How to install packages offline?
What's the best way to download a python package and it's dependencies from pypi for offline installation on another machine? Is there any easy way to do this with pip or easy_install? I'm trying to install the requests library on a FreeBSD box that is not connected to the internet.
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Difference between == and ===
In swift there seem to be two equality operators: the double equals ( == ) and the triple equals ( === ), what is the difference between the two?
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What is the difference between shallow copy, deepcopy and normal assignment operation?
...wards the existing object. The docs explain the difference between shallow and deep copies:
The difference between shallow and deep copying is only relevant for
compound objects (objects that contain other objects, like lists or
class instances):
A shallow copy constructs a new compo...
How to delete duplicates on a MySQL table?
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Notice: this would keep the oldest duplicate record and would erase the newer ones. If you want to keep the newest you cannot do this with ALTER IGNORE.
– Haralan Dobrev
Oct 1 '12 at 10:26
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What is a lambda expression in C++11?
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The problem
C++ includes useful generic functions like std::for_each and std::transform, which can be very handy. Unfortunately they can also be quite cumbersome to use, particularly if the functor you would like to apply is unique to the particular function.
#include <algorithm>
#inclu...
What does -1 mean in numpy reshape?
... (-1,3) but not (-1, -1)). It simply means that it is an unknown dimension and we want numpy to figure it out. And numpy will figure this by looking at the 'length of the array and remaining dimensions' and making sure it satisfies the above mentioned criteria
Now see the example.
z = np.array([[...
Why does this go into an infinite loop?
...ew MutableInt(valueBeforeIncrement);
}
Right? Increment the value passed and return the original value: that's the definition of the postincrement operator.
Now, let's see how this behavior plays out in your example code:
MutableInt x = new MutableInt();
x = postIncrement(x);
postIncrement(x) ...
Finding quaternion representing the rotation from one vector to another
I have two vectors u and v. Is there a way of finding a quaternion representing the rotation from u to v?
7 Answers
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How does the bitwise complement operator (~ tilde) work?
...representation of a number, taking its complement (inverting all the bits) and adding one. Two starts as 0000 0010, and by inverting the bits we get 1111 1101. Adding one gets us the result above. The first bit is the sign bit, implying a negative.
So let's take a look at how we get ~2 = -3:
Here's ...