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What is a “context bound” in Scala?
... the new features of Scala 2.8 are context bounds. What is a context bound and where is it useful?
4 Answers
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How to get different colored lines for different plots in a single figure?
...x)
plt.plot(x, 2 * x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)
plt.show()
And, as you may already know, you can easily add a legend:
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(10)
plt.plot(x, x)
plt.plot(x, 2 * x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)
plt.legend(['y = x', ...
Do HTML WebSockets maintain an open connection for each client? Does this scale?
... line of communication with the server. I'm just wondering how that scales and how many open WebSocket connections a server can handle. Maybe leaving those connections open isn't a problem in reality, but it feels like it is.
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Strange, unexpected behavior (disappearing/changing values) when using Hash default value, e.g. Hash
...ior applies to any default value that is subsequently mutated (e.g. hashes and strings), not just arrays.
TL;DR: Use Hash.new { |h, k| h[k] = [] } if you want the most idiomatic solution and don’t care why.
What doesn’t work
Why Hash.new([]) doesn’t work
Let’s look more in-depth at why...
Logging levels - Logback - rule-of-thumb to assign log levels
..., so my answer is biased towards looking at it from a production support standpoint; that said, we assign roughly as follows:
error: the system is in distress, customers are probably being affected (or will soon be) and the fix probably requires human intervention. The "2AM rule" applies here- if...
postgresql COUNT(DISTINCT …) very slow
...ount int not null), using triggers. But your write performance will suffer and if you update multiple x values in single transaction then you'd need to do this in some explicit order to avoid possible deadlock.
share
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Explain ExtJS 4 event handling
I've recently started learning ExtJS, and have trouble understanding how to handle Events. I have no experience of any previous versions of ExtJS.
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How do I test which class an object is in Objective-C?
...edited Feb 8 '17 at 9:02
Muruganandham K
5,01155 gold badges2929 silver badges6060 bronze badges
answered Jan 13 '10 at 10:48
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What is the difference between “#!/usr/bin/env bash” and “#!/usr/bin/bash”?
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Running a command through /usr/bin/env has the benefit of looking for whatever the default version of the program is in your current environment.
This way, you don't have to look for it in a specific place on the system, as those paths ma...
How do I call Objective-C code from Swift?
...t
If you have an existing class that you'd like to use, perform Step 2 and then skip to Step 5. (For some cases, I had to add an explicit #import <Foundation/Foundation.h to an older Objective-C File.)
Step 1: Add Objective-C Implementation -- .m
Add a .m file to your class, and name it Cu...