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How do I check if a list is empty?
...cMahon - it's a trade-off between explicitness and type flexibility. generally, "being explicit" means not doing "magical" things. on the other hand, "duck typing" means working with more general interfaces, rather than explicitly checking for types. so something like if a == [] is forcing a part...
How do I migrate a model out of one django app and into a new one?
... that one of these models should be in a separate app. I do have south installed for migrations, but I don't think this is something it can handle automatically. How can I migrate one of the models out of the old app into a new one?
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How to initialize a private static const map in C++?
... int>’ as ‘this’ argument of ‘std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](const key_type&) [with _Key = int; _Tp = int; _Compare = std::less<int>; _Alloc = std::allocator<std::pair<const int, int>...
What are the use cases of Graph-based Databases (http://neo4j.org/)? [closed]
...mport some of their own data and graft it on top of our model, it could usually be done on site by the sales rep. Flexibility also helped when we were designing a new feature, saving us from trying to squeeze new data into a rigid data model.
Having a weird database let us build a lot of our other ...
How do I raise the same Exception with a custom message in Python?
...ssign a special meaning to the elements of this tuple, while others are usually called only with a single string giving an error message.". So the code won't work arg[0] is not an error message (it could be an int, or it could be a string representing a file name).
– Trent
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Will using 'var' affect performance?
...ay have chosen an Interface or parent type if you were to set the type manually.
Update 8 Years Later
I need to update this as my understanding has changed. I now believe it may be possible for var to affect performance in the situation where a method returns an interface, but you would have used a...
How to check version of python modules?
I just installed the python modules: construct and statlib with setuptools like this:
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Access data in package subdirectory
...robust code that can access the subdirectory regardless of where it is installed on the user's system.
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How can you determine a point is between two other points on a line segment?
Let's say you have a two dimensional plane with 2 points (called a and b) on it represented by an x integer and a y integer for each point.
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Algorithm to compare two images
...t finds 4% of positives in our test data. However, one algorithm may find all the matches, but also have a large 20% false positive rate, so there are several ways to rate your algorithms.
The test data should attempt to be designed to cover as many types of dynamics as possible that you would exp...