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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
When using summarise with plyr 's ddply function, empty categories are dropped by default. You can change this behavior by adding .drop = FALSE . However, this doesn't work when using summarise with dplyr . Is there another way to keep empty categories in the result?
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How to generate random SHA1 hash to use as ID in node.js?
I am using this line to generate a sha1 id for node.js:
4 Answers
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How can I reverse a list in Python?
How can I do the following in Python?
35 Answers
35
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How to display a specific user's commits in svn log?
How to display a specific user's commits in svn? I didn't find any switches for that for svn log.
11 Answers
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Difference between return and exit in Bash functions
What is the difference between the return and exit statement in Bash functions with respect to exit codes?
10 Answers
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How do you display JavaScript datetime in 12 hour AM/PM format?
How do you display a JavaScript datetime object in the 12 hour format (AM/PM)?
25 Answers
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Checking if an object is null in C#
I would like to prevent further processing on an object if it is null.
17 Answers
17
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How do I obtain crash-data from my Android application?
How can I get crash data (stack traces at least) from my Android application? At least when working on my own device being retrieved by cable, but ideally from any instance of my application running on the wild so that I can improve it and make it more solid.
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Sending files using POST with HttpURLConnection
Since the Android developers recommend to use the HttpURLConnection class, I was wondering if anyone can provide me with a good example on how to send a bitmap "file" (actually an in-memory stream) via POST to an Apache HTTP server. I'm not interested in cookies or authentication or anything com...