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Adding a column to a data.frame
...xt, [[.data.frame.
Data frames can be indexed in several modes. When [ and [[ are used with a single vector index (x[i] or x[[i]]), they index the data frame as if it were a list.
my.dataframe["new.col"] <- a.vector
my.dataframe[["new.col"]] <- a.vector
The data.frame method for $, ...
Release generating .pdb files, why?
...even in the same order as) the generated assembly code. PDB files help you and the debugger out, making post-mortem debugging significantly easier.
You make the point that if your software is ready for release, you should have done all your debugging by then. While that's certainly true, there are ...
What do hjust and vjust do when making a plot using ggplot?
...lot using ggplot, I spend a little while trying different values for hjust and vjust in a line like
2 Answers
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Does C++ support 'finally' blocks? (And what's this 'RAII' I keep hearing about?)
...lock()
{
m_.release();
}
};
// A class which uses 'mutex' and 'lock' objects
class foo
{
mutex mutex_; // mutex for locking 'foo' object
public:
void bar()
{
lock scopeLock(mutex_); // lock object.
foobar(); // an operation which may throw an exception
...
Google Maps v3 - limit viewable area and zoom level
...a certain area? I want to allow displaying only some area (e.g. a country) and disallow the user to slide elsewhere. Also I want to restrict the zoom level - e.g. only between levels 6 and 9. And I want to use all the base map types.
...
What can I use instead of the arrow operator, `->`?
... them inconsistently. Becomes really annoying when you work with templates and don't know the precise type.
– Konrad Rudolph
Oct 21 '08 at 10:15
1
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Select N random elements from a List in C#
I need a quick algorithm to select 5 random elements from a generic list. For example, I'd like to get 5 random elements from a List<string> .
...
Double vs. BigDecimal?
I have to calculate some floating point variables and my colleague suggest me to use BigDecimal instead of double since it will be more precise. But I want to know what it is and how to make most out of BigDecimal ?
...
jQuery Popup Bubble/Tooltip [closed]
...ng to make a "bubble" that can popup when the onmouseover event is fired and will stay open as long as the mouse is over the item that threw the onmouseover event OR if the mouse is moved into the bubble. My bubble will need to have all manners of HTML and styling including hyperlinks, images, e...
How many Activities vs Fragments?
...he pattern used by the ActionBarSherlock Fragments Demo app (download here and source code here). The demo that most closely matches the tutorial mentioned in the question is the one called "Layout" in the app; or FragmentLayoutSupport in the source code.
In this demo, the logic has been moved out ...