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Running Bash commands in Python
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Don't use os.system. It has been deprecated in favor of subprocess. From the docs: "This module intends to replace several older modules and functions: os.system, os.spawn".
Like in your case:
bashCommand = "cwm --rdf test.rdf --ntriples > t...
Why does !{}[true] evaluate to true in JavaScript?
...cause plain {}[true] is parsed as an empty statement block (not an object literal) followed by an array containing true, which is true.
On the other hand, applying the ! operator makes the parser interpret {} as an object literal, so the following {}[true] becomes a member access that returns undef...
In C#, What is a monad?
... days. I have read a few articles / blog posts, but I can't go far enough with their examples to fully grasp the concept. The reason is that monads are a functional language concept, and thus the examples are in languages I haven't worked with (since I haven't used a functional language in depth). I...
What's “P=NP?”, and why is it such a famous question? [closed]
...ther P=NP is perhaps the most famous in all of Computer Science. What does it mean? And why is it so interesting?
6 Answers...
How efficient is locking an unlocked mutex? What is the cost of a mutex?
...n a low level language (C, C++ or whatever): I have the choice in between either having a bunch of mutexes (like what pthread gives me or whatever the native system library provides) or a single one for an object.
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Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
...o square root I've noticed something odd: using the SSE scalar operations, it is faster to take a reciprocal square root and multiply it to get the sqrt, than it is to use the native sqrt opcode!
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Is it safe to get values from a java.util.HashMap from multiple threads (no modification)?
There is a case where a map will be constructed, and once it is initialized, it will never be modified again. It will however, be accessed (via get(key) only) from multiple threads. Is it safe to use a java.util.HashMap in this way?
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Visual Studio 2010 isn't building before a run when there are code changes
I've been using using F5 (Start Debugging) for years to build the code (if its out of date), and then debug. This was working on VS 2010 also, however today it just start debugging without a build. Say I do a clean on the project, and then hit F5 instead of building it so it can run it throws an err...
Why don't self-closing script elements work?
...nce of an element whose content model is not EMPTY (for example, an empty title or paragraph) do not use the minimized form (e.g. use <p> </p> and not <p />).
XHTML DTD specifies script elements as:
<!-- script statements, which may include CDATA sections -->
<!ELEMENT ...
Is the Scala 2.8 collections library a case of “the longest suicide note in history”? [closed]
...ementation which is coming in the imminent 2.8 release. Those familiar with the library from 2.7 will notice that the library, from a usage perspective, has changed little. For example...
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