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Pandas: drop a level from a multi-level column index?
If I've got a multi-level column index:
7 Answers
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What is a None value?
I have been studying Python, and I read a chapter which describes the None value, but unfortunately this book isn't very clear at some points. I thought that I would find the answer to my question, if I share it there.
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Lambda function in list comprehensions
...output of the following two list comprehensions different, even though f and the lambda function are the same?
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What is the best CSS Framework and are they worth the effort?
Reading on another forum I've came across the world of CSS Frameworks. The one I've been specifically looking at is BluePrint . I was wondering if anyone else had come across CSS frameworks, suggest which is the best and if they are worth the effort?
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How can I select random files from a directory in bash?
I have a directory with about 2000 files. How can I select a random sample of N files through using either a bash script or a list of piped commands?
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Is it good practice to NULL a pointer after deleting it?
I'll start out by saying, use smart pointers and you'll never have to worry about this.
18 Answers
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Echo a blank (empty) line to the console from a Windows batch file [duplicate]
When outputting status messages to the console from a Windows batch file, I want to output blank lines to break up the output. How do I do this?
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Is it abusive to use IDisposable and “using” as a means for getting “scoped behavior” for exception
Something I often used back in C++ was letting a class A handle a state entry and exit condition for another class B , via the A constructor and destructor, to make sure that if something in that scope threw an exception, then B would have a known state when the scope was exited. This isn't pur...
Why does HTML5 form-validation allow emails without a dot?
I'm writing a very simple mock-up to demonstrate some HTML5 form-validation. However, I noticed the email validation doesn't check for a dot in the address, nor does it check for characters following said dot.
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How can the Euclidean distance be calculated with NumPy?
I have two points in 3D:
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