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How do I replace NA values with zeros in an R dataframe?

... mutate(myCol1 = if_else(is.na(myCol1), 0, myCol1)) Note: This works per selected column, if we need to do this for all column, see @reidjax's answer using mutate_each. share | improve this answer...
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Why is it bad style to `rescue Exception => e` in Ruby?

...IFT-ESC), go to the "processes" tab, find your process, right click it and select "End process". If you are working with someone else's program which is, for whatever reason, peppered with these ignore-exception blocks, then putting this at the top of the mainline is one possible cop-out: %W/INT Q...
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Setting environment variables via launchd.conf no longer works in OS X Yosemite/El Capitan/macOS Sie

... If the computer is restarted and "Reopen windows when logging back in" is selected, the reopened windows may not see the variables (Perhaps they are opened before the agent is run). Also, if you log in via ssh, the variables will not be set (so you'll need to set them in ~/.bash_profile). Finally, ...
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ASP.NET Web Site or ASP.NET Web Application?

...e solution is very fast, and you can always click on the Web Site node and select Build, if you’ve made changes. In an MVC Web Application project you have extra commands and dialogs for common tasks, like ‘Add View’, ‘Go To View’, ‘Add Controller’, etc. These are not available in an ...
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How do BitTorrent magnet links work?

...move last 'e' to compensate for bencoding return String.Join("", bytes.Select(b => b.ToString("X2"))); } As I understand it, this hash does not include any information on how to locate the tracker, the client needs to find this out through other means (the announce url provided). This is j...
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Learn C first before learning Objective-C [closed]

...also reduces the amount of material that has to be learned (and some of it selectively filtered out) to writing Objective-C programs. I do agree that you will want to learn most, if not all, of the underlying C features, but many can be deferred until a solid grasp of defining classes and method...
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initializer_list and move semantics

... std::forward<Ts>(ts)... }; } }; // // delegation function which selects the correct maker // template<class Array, class...Ts> auto make(Ts&&...ts) { auto m = maker<Array>(); return m(std::forward<Ts>(ts)...); } // vectors and arrays of non-copyable types us...
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How line ending conversions work with git core.autocrlf between different operating systems

...ne of CRLF_BINARY, CRLF_AUTO_INPUT or CRLF_AUTO_CRLF is selected - CRLF_BINARY : No processing of line endings. - CRLF_TEXT : attribute "text" is set, line endings are processed. - CRLF_TEXT_INPUT: attribute "input" or "eol=lf" is set. This implies text. - CRLF_TEXT_CRLF :...
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How do you specify the Java compiler version in a pom.xml file?

... Which way is "best"? This one is less verbose compared to the selected answer, but it seems sort of hidden. Even the Maven site documentation shows using the plugin. – mkobit Oct 15 '15 at 16:34 ...
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foreach vs someList.ForEach(){}

...INQ extension method that is more specific than ForEach(). See if Where(), Select(), Any(), All(), Max() or one of the many other LINQ methods doesn't already do what you want from the loop. share | ...