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Split a vector into chunks in R
...ails: I think all you need is seq_along(), split() and ceiling():
> d <- rpois(73,5)
> d
[1] 3 1 11 4 1 2 3 2 4 10 10 2 7 4 6 6 2 1 1 2 3 8 3 10 7 4
[27] 3 4 4 1 1 7 2 4 6 0 5 7 4 6 8 4 7 12 4 6 8 4 2 7 6 5
[53] 4 5 4 5 5 8 7 7 7 6 ...
:not(:empty) CSS selector is not working?
...
Being a void element, an <input> element is considered empty by the HTML definition of "empty", since the content model of all void elements is always empty. So they will always match the :empty pseudo-class, whether or not they have a value. Th...
make_unique and perfect forwarding
...rict static type checking (which is the main diff between C++ and C) is built on the idea of enforcing safety, via types. And for that, make_unique can simply be a class instead of function. For example, see my blog article from May 2010. It's also linked to from the discussion on Herb's blog.
...
How to check if a function exists on a SQL database
...
This is what SSMS uses when you script using the DROP and CREATE option
IF EXISTS (SELECT *
FROM sys.objects
WHERE object_id = OBJECT_ID(N'[dbo].[foo]')
AND type IN ( N'FN', N'IF', N'TF', N'FS', N'FT' ))
DROP FU...
Why can I initialize a List like an array in C#?
...you create as long as:
It implements IEnumerable (preferably IEnumerable<T>)
It has a method named Add(...)
What happens is the default constructor is called, and then Add(...) is called for each member of the initializer.
Thus, these two blocks are roughly identical:
List<int> a =...
How to set the context path of a web application in Tomcat 7.0
...
What you can do is the following;
Add a file called ROOT.xml in <catalina_home>/conf/Catalina/localhost/
This ROOT.xml will override the default settings for the root context of the tomcat installation for that engine and host (Catalina and localhost).
Enter the following to the RO...
Inserting HTML elements with JavaScript
...dChild(temp.firstChild);
}
return frag;
}
var fragment = create('<div>Hello!</div><p>...</p>');
// You can use native DOM methods to insert the fragment:
document.body.insertBefore(fragment, document.body.childNodes[0]);
Benefits:
You can use native DOM methods f...
Is there a performance impact when calling ToList()?
...
IEnumerable.ToList()
Yes, IEnumerable<T>.ToList() does have a performance impact, it is an O(n) operation though it will likely only require attention in performance critical operations.
The ToList() operation will use the List(IEnumerable<T> collect...
Equation (expression) parser with precedence?
...mbedding a parsing language like this in a language other than Haskell results in loads of syntactic cruft, by the way. I did this in C# and it works quite well but it is not so pretty and succinct.)
Notes:
1 Richard Stallman says, in Why you should not use Tcl
The principal lesson of Emacs is...
Disable Maven warning message - “Selected war files include a WEB-INF/web.xml which will be ignored”
...l is added to the project by other means, and should't be packaged by default):
<project>
...
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin<...