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How to prevent ifelse() from turning Date objects into numeric objects
I am using the function ifelse() to manipulate a date vector. I expected the result to be of class Date , and was surprised to get a numeric vector instead. Here is an example:
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Most efficient method to groupby on an array of objects
What is the most efficient way to groupby objects in an array?
43 Answers
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How to get my IP address programmatically on iOS/macOS?
I would like to obtain my iPad's IP address programmatically.
How can I query the networking subsystem to find out what my IPv4 (and IPv6) addresses are?
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Using smart pointers for class members
I'm having trouble understanding the usage of smart pointers as class members in C++11. I have read a lot about smart pointers and I think I do understand how unique_ptr and shared_ptr / weak_ptr work in general. What I don't understand is the real usage. It seems like everybody recommends using...
How can I prevent the “You have mixed tabs and spaces. Fix this?” message?
Any time I paste code into my .cs file, I get the dreaded "You have mixed tabs and spaces. Fix this?" message. It has three options:
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C++0x has no semaphores? How to synchronize threads?
...thout semaphores? There are already some questions on Stack Overflow regarding the use of semaphores. I use them (posix semaphores) all the time to let a thread wait for some event in another thread:
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OS X Bash, 'watch' command
I'm looking for the best way to duplicate the Linux 'watch' command on Mac OS X. I'd like to run a command every few seconds to pattern match on the contents of an output file using 'tail' and 'sed'.
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How to send commands when opening a tmux session inside another tmux session?
...efix command can be used to send your prefix keystroke to (the process running in) the active pane. By default, the prefix is C-b and C-b is bound to send-prefix (so that hitting it twice sends a single C-b to the active pane). This is just what we need to access the bindings of the inner tmux insta...
How to link godaddy domain with AWS Elastic Beanstalk environment?
I'm running into this problem trying to link my Godaddy domain with an AWS Elastic Beanstalk instance . I found a lot of documentation on how to link an EC2 instance with a domain on Godaddy but not for Elastic Beanstalk instance. So I ended up with this URL: www.MY_SITE.elasticbeanstalk.com
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How to make a JSONP request from Javascript without JQuery?
Can I make a cross-domain JSONP request in JavaScript without using jQuery or other external library? I would like to use JavaScript itself and then parse the data and make it an object so I could use it. Do I have to use an external library? If not, how can I do it?
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