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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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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!...
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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How do I update an entity using spring-data-jpa?
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Identity of entities is defined by their primary keys. Since firstname and lastname are not parts of the primary key, you cannot tell JPA to treat Users with the same firstnames and lastnames as equal if they have different userIds.
So, if you want to update a User identified by its firstname a...
How can I test https connections with Django as easily as I can non-https connections using 'runserv
I have an application that uses "secure" cookies and want to test it's functionality without needing to set up a complicated SSL enabled development server. Is there any way to do this as simply as I can test non-encrypted requests using ./manage.py runserver ?
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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...
Which is faster : if (bool) or if(int)?
The above topic made me do some experiments with bool and int in if condition. So just out of curiosity I wrote this program:
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A simple explanation of Naive Bayes Classification
I am finding it hard to understand the process of Naive Bayes, and I was wondering if someone could explain it with a simple step by step process in English. I understand it takes comparisons by times occurred as a probability, but I have no idea how the training data is related to the actual datase...
How do I delete NuGet packages that are not referenced by any project in my solution?
Somehow during the upgrade to VS2012 and .NET 4.5, I've managed to get NuGet confused. There are packages that appear in the package manager (and the packages folder) that I cannot delete (I believe they are legacy ASP.NET NuGet packages that have been replaced with new package names with the new v...
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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