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Mean per group in a data.frame [duplicate]
... of columns, you could first get the names of all the numeric columns, and set those with .SDcols = numericVars, instead of having to try to name them all in the j column. Another instance is using := to assign values in place .SD := lapply(.SD, f)
– cnolte
Jul...
Http Basic Authentication in Java using HttpClient?
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HttpPost httpPost = new HttpPost("http://host:post/test/login");
httpPost.setHeader(HttpHeaders.AUTHORIZATION, "Basic " + encoding);
System.out.println("executing request " + httpPost.getRequestLine());
HttpResponse response = httpClient.execute(httpPost);
HttpEntity entity = response.getEntity();...
Markdown and including multiple files
Is there any markdown fork that allows you to reference other files, something like an includes file? Specifically, I want to create a separate markdown file with links that I call often but not always (call this B.md), then when I link by reference in the md file I'm writing (A.md), I'd like it to ...
Web workers without a separate Javascript file?
As far as I can tell, web workers need to be written in a separate JavaScript file, and called like this:
25 Answers
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What is the real overhead of try/catch in C#?
...sing non-resident code and data not normally in your application's working set.
for example, throwing the exception will require the CLR to find the location of the finally and catch blocks based on the current IP and the return IP of every frame until the exception is handled plus the filter bloc...
Scala: What is the difference between Traversable and Iterable traits in Scala collections?
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Install an apk file from command prompt?
I want to install a file using the Windows command line. First I want to build after compiling all the .jar files to create an .apk file for an Android application without using Eclipse.
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Differences between “BEGIN RSA PRIVATE KEY” and “BEGIN PRIVATE KEY”
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How to convert date to timestamp?
I want to convert date to timestamp, my input is 26-02-2012 . I used
13 Answers
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How do I concatenate or merge arrays in Swift?
If there are two arrays created in swift like this:
12 Answers
12
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