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JOIN queries vs multiple queries
Are JOIN queries faster than several queries? (You run your main query, and then you run many other SELECTs based on the results from your main query)
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Why does Math.round(0.49999999999999994) return 1?
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Summary
In Java 6 (and presumably earlier), round(x) is implemented as floor(x+0.5).1 This is a specification bug, for precisely this one pathological case.2 Java 7 no longer mandates this broken implementation.3
The problem
0.5+0.49999999...
Set Colorbar Range in matplotlib
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Using vmin and vmax forces the range for the colors. Here's an example:
import matplotlib as m
import matplotlib.pyplot as plt
import numpy as np
cdict = {
'red' : ( (0.0, 0.25, .25), (0.02, .59, .59), (1., 1., 1.)),
'green':...
Why does sys.exit() not exit when called inside a thread in Python?
...a stupid question, but I'm testing out some of my assumptions about Python and I'm confused as to why the following code snippet would not exit when called in the thread, but would exit when called in the main thread.
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What are C++ functors and their uses?
...about functors in C++. Can someone give me an overview as to what they are and in what cases they would be useful?
14 Answe...
Difference between `const shared_ptr` and `shared_ptr`?
...const T> p; ---> const T * const p; <=> T const * const p; : p and *p are const.
The same holds for weak_ptr and unique_ptr.
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What is the most efficient Java Collections library? [closed]
... lot of functionality over the normal collections in the JDK.
Personally (and I'm biased) I love Guava (including the former Google Java Collections project). It makes various tasks (including collections) a lot easier, in a way which is at least reasonably efficient. Given that collection operatio...
Javascript reduce on array of objects
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After the first iteration your're returning a number and then trying to get property x of it to add to the next object which is undefined and maths involving undefined results in NaN.
try returning an object contain an x property with the sum of the x properties of the parame...
Differences between distribute, distutils, setuptools and distutils2?
...e on Python packaging issues, remember to look at the date of publication, and don't trust out-of-date information.
The Python Packaging User Guide is worth a read. Every page has a "last updated" date displayed, so you can check the recency of the manual, and it's quite comprehensive. The fact tha...
How can I mock dependencies for unit testing in RequireJS?
...ndencies instead of loading the actual dependencies. I am using requirejs, and the code for my module looks something like this:
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