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Apply multiple functions to multiple groupby columns
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The second half of the currently accepted answer is outdated and has two deprecations. First and most important, you can no longer pass a dictionary of dictionaries to the agg groupby method. Second, never use .ix.
If you desire to work with two separate columns at the same time I wou...
How to check BLAS/LAPACK linkage in NumPy and SciPy?
I am builing my numpy/scipy environment based on blas and lapack more or less based on this walk through.
5 Answers
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Difference between MEAN.js and MEAN.io
... noticed that there are two different stacks with either their own website and installation methods: mean.js and mean.io. So I came up asking myself this question: "Which one do I use?".
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How can I scale the content of an iframe?
...ow can I scale the content of an iframe (in my example it is an HTML page, and is not a popup) in a page of my web site?
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Fast permutation -> number -> permutation mapping algorithms
...you have n possibilities, so you can describe this with a number between 0 and n-1. For the position that the next element ends up at, you have n-1 remaining possibilities, so you can describe this with a number between 0 and n-2.
Et cetera until you have n numbers.
As an example for n = 5, consid...
Is it better to call ToList() or ToArray() in LINQ queries?
...lare it. This is usually because I need to iterate over it multiple times and it is expensive to compute. For example:
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How do you round a floating point number in Perl?
...f perldoc -q round
Does Perl have a round() function? What about ceil() and floor()?
Trig functions?
Remember that int() merely truncates toward 0. For rounding to a certain number of digits, sprintf() or printf() is usually the easiest
route.
printf("%.3f", 3.1415926535); # prints 3...
Empty arrays seem to equal true and false at the same time
...t (Array is instance of Object in JS) will check if the object is present, and returns true/false.
When you call if (arr == false) you compare values of this object and the primitive false value. Internally, arr.toString() is called, which returns an empty string "".
This is because toString cal...
CSS: bolding some text without changing its container's size
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I needed a css-only solution and this is the answer.
– JCasso
Jun 27 '13 at 8:00
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Ruby on Rails and Rake problems: uninitialized constant Rake::DSL
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A tweet from DHH earlier. Rake .9.0 breaks Rails and several other things, you need to:
gem "rake", "0.8.7"
in your Gemfile.
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