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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...
What is this weird colon-member (“ : ”) syntax in the constructor?
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It's a member initialization list. You should find information about it in any good C++ book.
You should, in most cases, initialize all member objects in the member initialization list (however, do note the exceptions liste...
PostgreSQL: Difference between text and varchar (character varying)
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There is no difference, under the hood it's all varlena (variable length array).
Check this article from Depesz: http://www.depesz.com/index.php/2010/03/02/charx-vs-varcharx-vs-varchar-vs-text/
A couple of highlights:
To sum it all up:
char(n) – ta...
Convert a PHP script into a stand-alone windows executable
I want to automate a fairly simple task. For this I have written a small PHP script which I run from the command line using PHP-CLI. Now I want to hand over this script to someone but I do not want to:
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What is the difference/usage of homebrew, macports or other package installation tools? [closed]
I've just recently switched to a Mac from Ubuntu. I was disappointed that mac doesn't have the convenient sudo apt-get in Ubuntu. I've heard that I should use homebrew but I'm not exactly sure what homebrew or macports does?
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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...
C++ performance vs. Java/C#
...ding is that C/C++ produces native code to run on a particular machine architecture. Conversely, languages like Java and C# run on top of a virtual machine which abstracts away the native architecture. Logically it would seem impossible for Java or C# to match the speed of C++ because of this inte...
How exactly does tail recursion work?
I almost understand how tail recursion works and the difference between it and a normal recursion. I only don't understand why it doesn't require stack to remember its return address.
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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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