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Prepend a level to a pandas MultiIndex
I have a DataFrame with a MultiIndex created after some grouping:
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Setup RSpec to test a gem (not Rails)
...pretty easy with the added generator of rspec-rails to setup RSpec for testing a Rails application. But how about adding RSpec for testing a gem in development?
I am not using jeweler or such tools. I just used Bundler ( bundle gem my_gem ) to setup the structure for the new gem and edit the *.gemsp...
What is the lifetime of a static variable in a C++ function?
If a variable is declared as static in a function's scope it is only initialized once and retains its value between function calls. What exactly is its lifetime? When do its constructor and destructor get called?
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Does JavaScript have “Short-circuit” evaluation?
...like to know if JavaScript has "short-circuit" evaluation like && Operator in C#. If not, I would like to know if there is a workaround that makes sense to adopt.
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How to pass object with NSNotificationCenter
I am trying to pass an object from my app delegate to a notification receiver in another class.
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Memory management in Qt?
I'm quite new to Qt and am wondering on some basic stuff with memory management and the life of objects. When do I need to delete and/or destroy my objects? Is any of this handled automatically?
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Xcode doesn't show the line that causes a crash
Every time my app crashes Xcode highlights the UIApicationMain() call in the main() function as the line that caused the crash. In some cases that used to be normal (segmentation fault for example) but the crash I am trying to deal with is a simple SIGABRT with detailed information logged in the con...
How can I call a custom Django manage.py command directly from a test driver?
...py command that does a backend operation on a database table. How would I invoke the management command directly from code?
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What's Pros and Cons: putting javascript in head and putting just before the body close
...f javascript and web development books/articles says that you must put CSS in the head tag and javascript at the bottom of the page.
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python requests file upload
I'm performing a simple task of uploading a file using Python requests library. I searched Stack Overflow and no one seemed to have the same problem, namely, that the file is not received by the server:
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