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C++: What is the size of an object of an empty class?
...can be 1 because alignment doesn't matter here, as there is nothing to actually look at.
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Remove duplicated rows
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Do note that this will remove all the columns except for the three first ones.
– GuillaumeL
Apr 1 '19 at 13:47
add a comment
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R memory management / cannot allocate vector of size n Mb
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Consider whether you really need all this data explicitly, or can the matrix be sparse? There is good support in R (see Matrix package for e.g.) for sparse matrices.
Keep all other processes and objects in R to a minimum when you need to make obj...
Where does git config --global get written to?
...Vascellaro points out in the comments,
it will work with non-standard install locations. (i.e. Git Portable)
(like the latest PortableGit-2.14.2-64-bit.7z.exe, which can be uncompressed anywhere you want)
Original answer (2010)
From the docs:
--global
For writing options: write to global ~/.gitc...
How do SQL EXISTS statements work?
...hen tries to match this 'true/false' condition with outerquery." is what really cleared it up for me, I keep thinking that's how subqueries work (and many times they do), but what you said makes sense because the subquery relies on the outer query and therefore must be executed once per row
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Create batches in linq
...e into sized buckets (MoreLINQ is available as a NuGet package you can install):
int size = 10;
var batches = sequence.Batch(size);
Which is implemented as:
public static IEnumerable<IEnumerable<TSource>> Batch<TSource>(
this IEnumerable<TSource> source,...
Subset of rows containing NA (missing) values in a chosen column of a data frame
...ated. THe point is to use is.na, I wrongly interpreted you wanted to check all variables.
– Joris Meys
Nov 2 '11 at 21:34
3
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Clear Text Selection with JavaScript
... window.getSelection().empty();
} else if (window.getSelection().removeAllRanges) { // Firefox
window.getSelection().removeAllRanges();
}
} else if (document.selection) { // IE?
document.selection.empty();
}
Credit to Mr. Y.
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Installing MSBuild 4.0 without Visual Studio 2010
I installed .NET 4.0 and VS 2010 RC on my laptop and MSBuild was automatically installed. I was hoping to build a continuous integration server by just installing the .NET SDK without VS 2010, so I downloaded the .NET 4.0 Framework from Microsoft at this link . Unfortunately, it doesn't appear to...
HTML5 record audio to file
...ailable at: http://webaudiodemos.appspot.com/AudioRecorder/index.html
It allows you to record audio in the browser, then gives you the option to export and download what you've recorded.
You can view the source of that page to find links to the javascript, but to summarize, there's a Recorder obj...