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Order data frame rows according to vector with specific order
... positions of (first) matches of its first argument
in its second.
Therefore match finds the row numbers that matches target's elements, and then we return df in that order.
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Iterate over object keys in node.js
...lowing, however it will also load all the keys into memory
Object.keys(o).forEach(function(key) {
var val = o[key];
logic();
});
However since Object.keys is a native method it may allow for better optimisation.
Benchmark
As you can see Object.keys is significantly faster. Whether the actua...
Catch-22 prevents streamed TCP WCF service securable by WIF; ruining my Christmas, mental health
...'m looking at you, MTOM1) due to a fundamental issue in how it fails to perform preauthentication the way most people would think that should work (it only affects subsequent requests for that channel, not the first request) Ok, so this is not exactly your issue but please follow along as I will get...
Does Entity Framework Code First support stored procedures?
...
EDIT: My original answer for EF4.1 (below) is now out of date. Please see the answer below from Diego Vega (who works on the EF team at Microsoft)!
@gsharp and Shawn Mclean: Where are you getting this information? Don't you still have access to...
How can I brew link a specific version?
...
The usage info:
Usage: brew switch <formula> <version>
Example:
brew switch mysql 5.5.29
You can find the versions installed on your system with info.
brew info mysql
And to see the available versions to install, you can provide a dud version n...
Plotting time in Python with Matplotlib
I have an array of timestamps in the format (HH:MM:SS.mmmmmm) and another array of floating point numbers, each corresponding to a value in the timestamp array.
...
MIN/MAX vs ORDER BY and LIMIT
...arge table, there would likely be a significant difference in percieved performance. As a meaningless data point, MIN() took .36s while SORT and LIMIT took .84s against a 106,000 row table on my dev server.
If, however, you're looking at an indexed column, the difference is harder to notice (meani...
Is it possible to assign numeric value to an enum in Java?
...rectly as EXIT_CODE.A.numVal (I prefer the name 'value'), without the need for an accessor method. Since it's final, it can only be set in the constructor. IMO it leads to slightly cleaner code, but it's mostly a matter of preference, I suppose. Using a final variable saves you one method definit...
Visual Studio support for new C / C++ standards?
...ly based on interest from our users. Where we’ve received many requests for certain C99 features, we’ve tried to implement them (or analogues). A couple examples are variadic macros, long long, __pragma, __FUNCTION__, and __restrict. If there are other C99 features that you’d find useful in...
nil detection in Go
...ault initialization. Each element of such a value is set to the zero value for its type: false for booleans, 0 for integers, 0.0 for floats, "" for strings, and nil for pointers, functions, interfaces, slices, channels, and maps. This initialization is done recursively, so for instance each element ...