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How do you implement a class in C? [closed]
Assuming I have to use C (no C++ or object oriented compilers) and I don't have dynamic memory allocation, what are some techniques I can use to implement a class, or a good approximation of a class? Is it always a good idea to isolate the "class" to a separate file? Assume that we can preallocate t...
What are Unwind segues for and how do you use them?
iOS 6 and Xcode 4.5 has a new feature referred to as "Unwind Segue":
6 Answers
6
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Why is a ConcurrentModificationException thrown and how to debug it
... (a HashMap used indirectly by the JPA, it so happens), but apparently randomly the code throws a ConcurrentModificationException . What is causing it and how do I fix this problem? By using some synchronization, perhaps?
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Get time difference between two dates in seconds
...he explanation
You need to call the getTime() method for the Date objects, and then simply subtract them and divide by 1000 (since it's originally in milliseconds). As an extra, when you're calling the getDate() method, you're in fact getting the day of the month as an integer between 1 and 31 (not ...
postgresql - replace all instances of a string within text field
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Hi guys, I like your answer and explanation, it is really helpful. Could you please add an example using regexp_replace? Thanks!
– Wim Feijen
Oct 22 '14 at 16:09
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How can I generate random alphanumeric strings?
How can I generate a random 8 character alphanumeric string in C#?
33 Answers
33
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Does ARC support dispatch queues?
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The short answer: YES, ARC retains and releases dispatch queues.
And now for the long answer…
If your deployment target is lower than iOS 6.0 or Mac OS X 10.8
You need to use dispatch_retain and dispatch_release on your queue. ARC does not manage ...
Advantages of std::for_each over for loop
...h only seems to hinder the readability of code. Why do then some coding standards recommend its use?
21 Answers
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Setting different color for each series in scatter plot on matplotlib
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I don't know what you mean by 'manually'. You can choose a colourmap and make a colour array easily enough:
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.cm as cm
x = np.arange(10)
ys = [i+x+(i*x)**2 for i in range(10)]
colors = cm.rainbow(np.linspace(0, 1, len(ys)))
f...
What's the difference between Task.Start/Wait and Async/Await?
...g something
You are.
what is the difference between doing Task.Wait and await task?
You order your lunch from the waiter at the restaurant. A moment after giving your order, a friend walks in and sits down next to you and starts a conversation. Now you have two choices. You can ignore your ...