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Array.Copy vs Buffer.BlockCopy
Array.Copy and Buffer.BlockCopy both do the same thing, but BlockCopy is aimed at fast byte-level primitive array copying, whereas Copy is the general-purpose implementation. My question is - under what circumstances should you use BlockCopy ? Should you use it at any time when you are copyi...
Equivalent of LIMIT and OFFSET for SQL Server?
In PostgreSQL there is the Limit and Offset keywords which will allow very easy pagination of result sets.
16 Answers
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Best way to test for a variable's existence in PHP; isset() is clearly broken
...l scope variables as well, on can do a $defined_vars = get_defined_vars(); and then test via array_key_exists('v', $defined_vars);.
– Henrik Opel
Sep 27 '10 at 16:01
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Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
I've been profiling some of our core math on an Intel Core Duo, and while looking at various approaches to 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!...
What are the pros and cons of both Jade and EJS for Node.js templating? [closed]
Jade versus EJS, what are the pros and cons of each and what purposes are each designed for?
2 Answers
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When to use references vs. pointers
I understand the syntax and general semantics of pointers versus references, but how should I decide when it is more-or-less appropriate to use references or pointers in an API?
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How to install packages offline?
What's the best way to download a python package and it's dependencies from pypi for offline installation on another machine? Is there any easy way to do this with pip or easy_install? I'm trying to install the requests library on a FreeBSD box that is not connected to the internet.
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Difference between modes a, a+, w, w+, and r+ in built-in open function?
...tion, what is the exact difference between the modes w , a , w+ , a+ , and r+ ?
6 Answers
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Why is my variable unaltered after I modify it inside of a function? - Asynchronous code reference
...nicity.
Forewords
This topic has been iterated at least a couple of thousands of times, here, in Stack Overflow. Hence, first off I'd like to point out some extremely useful resources:
@Felix Kling's answer to "How do I return the response from an asynchronous call?". See his excellent answer ex...
AWS Difference between a snapshot and AMI
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There are two types of AMIs (and corresponding instances):
instance-store (sometimes called S3-based). These are less common and I don't recommend them for beginners. An instance-store AMI is a copy of the root instance-store volume plus some metadat...