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Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
...l attempt and the following answer is no longer necessary.
You can use DT[order(-rank(x), y)].
x y v
1: c 1 7
2: c 3 8
3: c 6 9
4: b 1 1
5: b 3 2
6: b 6 3
7: a 1 4
8: a 3 5
9: a 6 6
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How to check if a string contains text from an array of substrings in JavaScript?
...Of(arr[i]) != -1) {
// str contains arr[i]
}
}
edit:
If the order of the tests doesn't matter, you could use this (with only one loop variable):
var str = "texttexttext";
var arr = ["asd", "ghj", "xtte"];
for (var i = arr.length - 1; i >= 0; --i) {
if (str.indexOf(arr[i]) != -...
Are Exceptions in C++ really slow
...l, mostly regardless of language, the two basic language features that are orders of magnitude slower than the rest, because they translate to calls of routines that handle complex data structures, are
exception throwing, and
dynamic memory allocation.
Happily in C++ one can often avoid both in ...
Singleton with Arguments in Java
...
You can add a configurable initialization method in order to separate instantiation from getting.
public class Singleton {
private static Singleton singleton = null;
private final int x;
private Singleton(int x) {
this.x = x;
}
public static Sing...
Laravel Eloquent: Ordering results of all()
I'm stuck on a simple task.
I just need to order results coming from this call
9 Answers
...
Changing the image source using jQuery
...will work with 2, 3, 5, 10, or 100 images... cycling through each image in order and restarting at the first image when the last image is reached.
Additionally, .attr() is used to get and set the "src" attribute of the images. To pick elements from among the $images object, I set $images as the jQu...
How do I install and use curl on Windows?
... environment), and you won't have to type the full pathname to curl.exe in order to run it.
– theglauber
Mar 1 '12 at 15:33
11
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PHP Session Security
...
There are a couple of things to do in order to keep your session secure:
Use SSL when authenticating users or performing sensitive operations.
Regenerate the session id whenever the security level changes (such as logging in). You can even regenerate the sessio...
Tricks to manage the available memory in an R session
...
That's a good technique. When files are run in a certain order like that, I often prefix them with a number: 1-load.r, 2-explore.r, 3-model.r - that way it's obvious to others that there is some order present.
– hadley
Sep 4 '09 at 13:02
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How to add custom method to Spring Data JPA
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Im using the following code in order to access generated find methods from my custom implementation. Getting the implementation through the bean factory prevents circular bean creation problems.
public class MyRepositoryImpl implements MyRepositoryExtensi...