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Convert data.frame column to a vector?
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I'm going to attempt to explain this without making any mistakes, but I'm betting this will attract a clarification or two in the comments.
A data frame is a list. When you subset a data frame using the name of a column and [, what you're getting is a sublist (or a sub d...
Pass Variables by Reference in Javascript
... alert("x is " + x + ", y is " + y); // "x is 1, y is 2"
In a language like C++, it's possible to do that because that language does (sort-of) have pass-by-reference.
edit — this recently (March 2015) blew up on Reddit again over a blog post similar to mine mentioned below, though in this case ...
Inheriting from a template class in c++
... of huge advantage to get the terminology straight because the way you speak about them determines the way to think about them.
Specifically, Area is not a template class, but a class template. That is, it is a template from which classes can be generated. Area<int> is such a class (it's not ...
Limitations of SQL Server Express
My hosting provider (Rackspace) is offering a fully managed dedicated server with SQL Server Web version () installed. My company handles web development, and has about 20+ clients using ASP.Net + SQL Server 2005.
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android TextView: setting the background color dynamically doesn't work
Setting the background color programatically of an android TextView doesn't seem to work.
I'm I missing something!
14 Ans...
How to center an iframe horizontally?
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Add display:block; to your iframe css.
div, iframe {
width: 100px;
height: 50px;
margin: 0 auto;
background-color: #777;
}
iframe {
display: block;
border-style:none;
}
<div>div</div>
<iframe src=...
gdb split view with code
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It's called the TUI (no kidding). Start for example with gdbtui or gdb -tui ...
Please also see this answer by Ciro Santilli. It wasn't available in 2012 to the best of my knowledge, but definitely worth a look.
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How to sort an array based on the length of each element?
I have an array like this:
8 Answers
8
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How does “this” keyword work within a function?
...t the this pointer is referring to the class on which the method was invoked, and not the object being created by the literal.
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Optimistic vs. Pessimistic locking
I understand the differences between optimistic and pessimistic locking. Now could someone explain to me when I would use either one in general?
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