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What's the fastest way to merge/join data.frames in R?
...(y) from main.d group by g1, g2"))
)
The outputs from the two benchmark call comparing the merge calculations are:
Joining by: x
test replications elapsed relative user.self sys.self user.child sys.child
3 data.table 1 0.34 1.000000 0.31 0.01 NA NA
2 ...
Formatting text in a TextBlock
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98
You can do this in XAML easily enough:
<TextBlock>
Hello <Bold>my</Bold> f...
Java resource as file
...
98
I had the same problem and was able to use the following:
// Load the directory as a resource
...
What is your most productive shortcut with Vim?
I've heard a lot about Vim , both pros and cons.
It really seems you should be (as a developer) faster with Vim than with any other editor.
I'm using Vim to do some basic stuff and I'm at best 10 times less productive with Vim.
...
What is the advantage of using forwarding references in range-based for loops?
...or<bool> v(10);
for (auto&& e : v)
e = true;
}
All that being said, I wouldn't code this way unless you knew you needed to satisfy such a use case. I.e. I wouldn't do this gratuitously because it does cause people to wonder what you're up to. And if I did do it, it woul...
What is the 'dynamic' type in C# 4.0 used for?
C# 4.0 introduced a new type called 'dynamic'. It all sounds good, but what would a programmer use it for?
10 Answers
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How to scale down a range of numbers with a known min and max value
...Range, maxRange);
console.log(scaled.toFixed(2));
}
0.00, 18.37, 48.98, 55.10, 85.71, 100.00
Edit:
I know I answered this a long time ago, but here's a cleaner function that I use now:
Array.prototype.scaleBetween = function(scaledMin, scaledMax) {
var max = Math.max.apply(Math, this);...
Difference between Pragma and Cache-Control headers?
... Cache-Control: no-cache has the same meaning for requests but is actually also defined for responses, meaning "If you want to use a cached copy of this in future, you must first check with me that it is up-to-date (i.e. perform revalidation)".
– clime
Mar...
Undefined behavior and sequence points
...the C++ standard. The C++11 and C++14 versions of the standard do not formally contain 'sequence points'; operations are 'sequenced before' or 'unsequenced' or 'indeterminately sequenced' instead. The net effect is essentially the same, but the terminology is different.
Disclaimer : Okay. This ...
What is the difference between Bower and npm?
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All package managers have many downsides. You just have to pick which you can live with.
History
npm started out managing node.js modules (that's why packages go into node_modules by default), but it works for the front-end...