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How to select the row with the maximum value in each group
...ve the data available both inside and outside the group data.frame. If you read the data in with read.table or something, you would need to use with because those column names would not be available outside the data.frame.
– MrFlick
Jul 4 '14 at 15:56
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Using node.js as a simple web server
...served to it but as a regular HTML page (i.e., same experience as when you read normal web pages).
32 Answers
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What is std::move(), and when should it be used?
...pens when T is, say, vector<int> of size n. In the first version you read and write 3*n elements, in the second version you basically read and write just the 3 pointers to the vectors' buffers, plus the 3 buffers' sizes. Of course, class T needs to know how to do the moving; your class should ...
Do HttpClient and HttpClientHandler have to be disposed between requests?
... results in memory leak for reference.
I'd also strongly suggest that you read the HttpClient chapter from Designing Evolvable Web APIs with ASP.NET for context on what is going on under the hood, particularly the "Lifecycle" section quoted here:
Although HttpClient does indirectly implement th...
Java: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification
... .pem are commonly used file extensions for the same file format. If you already have the file, just run the second command and pass it into the -file argument.
– Gabe Martin-Dempesy
Mar 14 '17 at 19:15
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Understanding Python super() with __init__() methods [duplicate]
...s of fun stuff can happen. See the standard docs on super if you haven't already.
Note that the syntax changed in Python 3.0: you can just say super().__init__() instead of super(ChildB, self).__init__() which IMO is quite a bit nicer. The standard docs also refer to a guide to using super() which ...
How to find what code is run by a button or element in Chrome using Developer Tools
... yes, I'm just finishing right now. FYI, if you didn't know it already, if you click the down left curly braces button (i.imgur.com/ALoMQkR.png) on a minified script, it will "beautify" it, and will work while debugging too.
– Carles Alcolea
May 7 '14...
How can I rename a field for all documents in MongoDB?
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@Steve name.last is not table.field. If you read the question, you can see that the name field holds an object.
– Marc Dingena
Oct 1 '15 at 8:31
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How to determine if a number is a prime with regex?
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The comment below gives better explanation. Please read it before you move on!
– Ivan Davidov
Sep 26 '15 at 21:54
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Embedding unmanaged dll into a managed C# dll
...;
byte[] buf = new byte[sz];
while (true)
{
int nRead = stm.Read(buf, 0, sz);
if (nRead < 1)
break;
outFile.Write(buf, 0, nRead);
}
}
}
catch
{
// This may happen if another process has already created and loaded the file.
...