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How to sort a dataframe by multiple column(s)
... code:
R> dd[with(dd, order(-z, b)), ]
b x y z
4 Low C 9 2
2 Med D 3 1
1 Hi A 8 1
3 Hi A 9 1
Edit some 2+ years later: It was just asked how to do this by column index. The answer is to simply pass the desired sorting column(s) to the order() function:
R> dd[order(-dd[,4], dd[,1]), ...
Which version of the git file will be finally used: LOCAL, BASE or REMOTE?
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edited Jun 21 '12 at 14:31
VonC
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ans...
Loop through an array in JavaScript
...e seen this anti-pattern so many times.
Anti-pattern:
const numbers = [1,2,3,4,5], doubled = [];
numbers.forEach((n, i) => { doubled[i] = n * 2 });
Proper use case of map:
const numbers = [1,2,3,4,5];
const doubled = numbers.map(n => n * 2);
console.log(doubled);
Also, if you are ...
How to make an alert dialog fill 90% of screen size?
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According to Android platform developer Dianne Hackborn in this discussion group post, Dialogs...
Is there a decorator to simply cache function return values?
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Starting from Python 3.2 there is a built-in decorator:
@functools.lru_cache(maxsize=100, typed=False)
Decorator to wrap a function with a memoizing callable that saves up to the maxsize most recent calls. It can save time when an expensive or...
How do I check if a property exists on a dynamic anonymous type in c#?
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edited Apr 5 '17 at 15:32
answered Mar 31 '12 at 14:58
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Is the size of C “int” 2 bytes or 4 bytes?
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How can I force a long string without any blank to be wrapped?
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Port 80 is being used by SYSTEM (PID 4), what is that?
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