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Relative frequencies / proportions with dplyr
Suppose I want to calculate the proportion of different values within each group. For example, using the mtcars data, how do I calculate the relative frequency of number of gears by am (automatic/manual) in one go with dplyr ?
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How to create a density plot in matplotlib?
In R I can create the desired output by doing:
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Why is null an object and what's the difference between null and undefined?
Why is null considered an object in JavaScript?
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Is it better to use std::memcpy() or std::copy() in terms to performance?
Is it better to use memcpy as shown below or is it better to use std::copy() in terms to performance? Why?
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CSS: Set a background color which is 50% of the width of the window
Trying to achieve a background on a page that is "split in two"; two colors on opposite sides (seemingly done by setting a default background-color on the body tag, then applying another onto a div that stretches the entire width of the window).
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Python: Append item to list N times
This seems like something Python would have a shortcut for. I want to append an item to a list N times, effectively doing this:
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C# Error: Parent does not contain a constructor that takes 0 arguments
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What is a “context bound” in Scala?
One of the new features of Scala 2.8 are context bounds. What is a context bound and where is it useful?
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Programmatically generate video or animated GIF in Python?
I have a series of images that I want to create a video from. Ideally I could specify a frame duration for each frame but a fixed frame rate would be fine too. I'm doing this in wxPython, so I can render to a wxDC or I can save the images to files, like PNG. Is there a Python library that will al...
How do I break out of nested loops in Java?
I've got a nested loop construct like this:
35 Answers
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