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Which @NotNull Java annotation should I use?
...ll of them in my code would be terrible to read. Any suggestions of which one is the 'best'? Here is the list of equivalent annotations I've found:
...
iphone Core Data Unresolved error while saving
...quirements try cleaning your build and delete the application from your iPhone Simulator/iPhone device. Your model change may conflict with the old model implementation.
Edit:
I almost forgot here's all the error codes that Core Data spits out:
Core Data Constants Reference
I had trouble with this...
Is there a way to get rid of accents and convert a whole string to regular letters?
...egular apart from using String.replaceAll() method and replacing letters one by one?
Example:
12 Answers
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How to calculate moving average using NumPy?
..., which may be is faster than FFT based methods:
EDIT Corrected an off-by-one wrong indexing spotted by Bean in the code. EDIT
def moving_average(a, n=3) :
ret = np.cumsum(a, dtype=float)
ret[n:] = ret[n:] - ret[:-n]
return ret[n - 1:] / n
>>> a = np.arange(20)
>>> m...
Why should casting be avoided? [closed]
...ts as well, and that gives (more or less) a fourth answer.
Since it's the one you didn't mention explicitly, I'll start with C. C casts have a number of problems. One is that they can do any of a number of different things. In some cases, the cast does nothing more than tell the compiler (in essenc...
Using generic std::function objects with member functions in one class
For one class I want to store some function pointers to member functions of the same class in one map storing std::function objects. But I fail right at the beginning with this code:
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Regex to match string containing two names in any order
...
Does anyone know why this would break (in JavaScript at least) when I try to search for strings starting with '#'? ^(?=.*\b#friday\b)(?=.*\b#tgif\b).*$ fails to match blah #tgif blah #friday blah but ^(?=.*\bfriday\b)(?=.*\btgif\b).*...
A monad is just a monoid in the category of endofunctors, what's the problem?
...ote is from Saunders Mac Lane in Categories for the Working Mathematician, one of the foundational texts of Category Theory. Here it is in context, which is probably the best place to learn exactly what it means.
But, I'll take a stab. The original sentence is this:
All told, a monad in X is just a...
What are the differences between numpy arrays and matrices? Which one should I use?
...nd b are numpy arrays, then a*b is the array
formed by multiplying the components element-wise:
c = np.array([[4, 3], [2, 1]])
d = np.array([[1, 2], [3, 4]])
print(c*d)
# [[4 6]
# [6 4]]
To obtain the result of matrix multiplication, you use np.dot (or @ in Python >= 3.5, as shown above):
pr...
Difference between clustered and nonclustered index [duplicate]
...eed to keep two issues apart:
1) the primary key is a logical construct - one of the candidate keys that uniquely and reliably identifies every row in your table. This can be anything, really - an INT, a GUID, a string - pick what makes most sense for your scenario.
2) the clustering key (the colu...