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Get statistics for each group (such as count, mean, etc) using pandas GroupBy?
I have a data frame df and I use several columns from it to groupby :
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How to make rounded percentages add up to 100%
Consider the four percentages below, represented as float numbers:
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Difference between method and function in Scala
I read Scala Functions (part of Another tour of Scala ). In that post he stated:
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How to crop an image in OpenCV using Python
How can I crop images, like I've done before in PIL, using OpenCV.
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How does !!~ (not not tilde/bang bang tilde) alter the result of a 'contains/included' Array method
...he comments at the jQuery inArray page here , there's an interesting declaration:
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How to locate a file in Solution Explorer in Visual Studio 2010?
I have a huge solution with multiple projects. Sometime I need to navigate to a file in Solution Explorer . Using the VS 2010 ' Navigate To ' feature I can open any file by name in Visual Studio 2010 but I want to be able to select the file in Solution Explorer as well?
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Generating random numbers in Objective-C
I'm a Java head mainly, and I want a way to generate a pseudo-random number between 0 and 74. In Java I would use the method:
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How do I concatenate two lists in Python?
How do I concatenate two lists in Python?
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How do you effectively model inheritance in a database?
What are the best practices for modeling inheritance in databases?
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Add number of days to a date
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This should be
echo date('Y-m-d', strtotime("+30 days"));
strtotime
expects to be given a string containing a US English date format and will try to parse that format into a Unix timestamp (the number of seconds since ...