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HashSet vs. List performance
It's clear that a search performance of the generic HashSet<T> class is higher than of the generic List<T> class. Just compare the hash-based key with the linear approach in the List<T> class.
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Enabling WiFi on Android Emulator
...ndroid emulator? I have tried to find this but everyone is confusing WiFi with 3G.
6 Answers
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UnicodeEncodeError: 'ascii' codec can't encode character u'\xa0' in position 20: ordinal not in rang
I'm having problems dealing with unicode characters from text fetched from different web pages (on different sites). I am using BeautifulSoup.
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When should null values of Boolean be used?
...n in a database, for example). The null value might mean "we don't know if it's true or false" in this context.
each time a method needs an Object as argument, and you need to pass a boolean value. For example, when using reflection or methods like MessageFormat.format().
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OwinStartup not firing
I had the OwinStartup configuration code working perfectly and then it stopped working. Unfortunately I'm not sure exactly what I did to get it to stop working and am having a really hard time figuring it out.
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What generates the “text file busy” message in Unix?
...r is accessing your file. Use lsof to check what other processes are using it. You can use kill command to kill it if needed.
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#ifdef replacement in the Swift language
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Yes you can do it.
In Swift you can still use the "#if/#else/#endif" preprocessor macros (although more constrained), as per Apple docs. Here's an example:
#if DEBUG
let a = 2
#else
let a = 3
#endif
Now, you must set the "DEBUG"...
Force R not to use exponential notation (e.g. e+10)?
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This is a bit of a grey area. You need to recall that R will always invoke a print method, and these print methods listen to some options. Including 'scipen' -- a penalty for scientific display. From help(options):
‘scipen’: i...
What does “static” mean in C?
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A static variable inside a function keeps its value between invocations.
A static global variable or a function is "seen" only in the file it's declared in
(1) is the more foreign topic if you're a newbie, so here's an example:
#include <stdio.h>
void foo()...
Fatal error in launcher: Unable to create process using “”C:\Program Files (x86)\Python33\python.exe
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it seems that
python -m pip install XXX
will work anyway (worked for me)
(see link by user474491)
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