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Are the shift operators () arithmetic or logical in C?
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When shifting left, there is no difference between arithmetic and logical shift. When shifting right, the type of shift depends on the type of the value being shifted.
(As background for those readers unfamiliar with the difference, a "logical" right shift by 1 bit shifts all the bits ...
Several ports (8005, 8080, 8009) required by Tomcat Server at localhost are already in use
... You can confirm this by going to http://localhost:8080 in your webbrowser and check if you get the Tomcat default home page or a Tomcat-specific 404 error page. Both are equally valid evidence that Tomcat runs fine; if it didn't, then you would have gotten a browser specific HTTP connection timeout...
Difference between variable declaration syntaxes in Javascript (including global variables)?
...gh in practical terms they're not usually big ones.
There's a fourth way, and as of ES2015 (ES6) there's two more. I've added the fourth way at the end, but inserted the ES2015 ways after #1 (you'll see why), so we have:
var a = 0; // 1
let a = 0; // 1.1 (new with ES2015)
const a = 0; //...
Search for executable files using find command
What type of parameter/flag can I use with the Unix find command so that I search executables?
10 Answers
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What are the differences and similarities between ffmpeg, libav, and avconv?
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Confusing messages
These messages are rather misleading and understandably a source of confusion. Older Ubuntu versions used Libav which is a fork of the FFmpeg project. FFmpeg returned in Ubuntu 15.04 "Vivid Vervet".
The fork was basically a non-amicable result of conflicting pe...
How dangerous is it to compare floating point values?
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First of all, floating point values are not "random" in their behavior. Exact comparison can and does make sense in plenty of real-world usages. But if you're going to use floating point you need to be aware of how it works. Erring on the side of assuming floating point ...
Why compile Python code?
...d you compile a Python script? You can run them directly from the .py file and it works fine, so is there a performance advantage or something?
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How to overload __init__ method based on argument type?
... reason it's neater is that there is no doubt about what type is expected, and you aren't forced to guess at what the caller intended for you to do with the datatype it gave you. The problem with isinstance(x, basestring) is that there is no way for the caller to tell you, for instance, that even th...
SQL SELECT WHERE field contains words
...e present, use this:
SELECT * FROM mytable
WHERE column1 LIKE '%word1%'
AND column1 LIKE '%word2%'
AND column1 LIKE '%word3%'
If you want something faster, you need to look into full text search, and this is very specific for each database type.
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Storing JSON in database vs. having a new column for each key
...ing user related data in my table - I have 2 columns - uid (primary key) and a meta column which stores other data about the user in JSON format.
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