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Unresolved reference issue in PyCharm
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Manually adding it as you have done is indeed one way of doing this, but there is a simpler method, and that is by simply telling pycharm that you want to add the src folder as a source root, and then adding the sources root to y...
Does SQLAlchemy have an equivalent of Django's get_or_create?
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That's basically the way to do it, there is no shortcut readily available AFAIK.
You could generalize it ofcourse:
def get_or_create(session, model, defaults=None, **kwargs):
instance = session.query(model).filter_by(**kwargs).firs...
Geometric Mean: is there a built-in?
...pplication I had in mind they are the same, but of course this is not generally true. Thus, if you want to include optional propagation of zeros, and treat the length(x) differently in the case of NA removal, the following is a slightly longer alternative to the function above.
gm_mean = function(x...
Oracle query to fetch column names
...tion_schema.COLUMNS is USER_TAB_COLS for tables owned by the current user, ALL_TAB_COLS or DBA_TAB_COLS for tables owned by all users.
Tablespace is not equivalent to a schema, neither do you have to provide the tablespace name.
Providing the schema/username would be of use if you want to query AL...
git + LaTeX workflow
...ve my work computer and my laptop, and I work on them both. I need to keep all the files synchronized between the two computers, and also would like to keep a revision history. I chose git as my DVCS, and I'm hosting my repository on my server. I'm also using Kile + Okular to do the editing. Kile do...
How to get the name of enumeration value in Swift?
... on each case to return a string literal. In addition, this works automatically for any enum, even if no raw-value type is specified.
debugPrint(_:) & String(reflecting:) can be used for a fully-qualified name:
debugPrint(city)
// prints "App.City.Melbourne" (or similar, depending on the full ...
Missing include “bits/c++config.h” when cross compiling 64 bit program on 32 bit in Ubuntu
...ying to cross compile to a 64 bit target. Based on my research, I have installed the g++-multilib package.
8 Answers
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Is it better to use std::memcpy() or std::copy() in terms to performance?
...y.
I wrote a C++ SHA-2 implementation. In my test, I hash 5 strings using all four SHA-2 versions (224, 256, 384, 512), and I loop 300 times. I measure times using Boost.timer. That 300 loop counter is enough to completely stabilize my results. I ran the test 5 times each, alternating between the m...
Iterating C++ vector from the end to the beginning
...;
i != my_vector.rend(); ++i ) {
}
rbegin()/rend() were especially designed for that purpose. (And yes, incrementing a reverse_interator moves it backward.)
Now, in theory, your method (using begin()/end() & --i) would work, std::vector's iterator being bidirectional, but remember,...
Is there an exponent operator in C#?
...o in most programs, and
it doesn't seem justified to add an
operator when calling Math.Pow() is
simple.
You asked:
Do I have to write a loop or include
another namespace to handle
exponential operations? If so, how do
I handle exponential operations using
non-integers?
Math.Pow supports double p...