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Determine the number of NA values in a column

...nt the number of NA values in a data frame column. Say my data frame is called df , and the name of the column I am considering is col . The way I have come up with is following: ...
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Reducing Django Memory Usage. Low hanging fruit?

...) Then point your browser at http://domain/_dozer/index to see a list of all your memory allocations. I'll also just add my voice of support for mod_wsgi. It makes a world of difference in terms of performance and memory usage over mod_python. Graham Dumpleton's support for mod_wsgi is outstand...
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Tool to Unminify / Decompress JavaScript [closed]

...iderMonkey and Rhino you can wrap any code into an anonymous function and call its toSource method, which will give you a nicely formatted source of the function. toSource also strips comments. E. g.: (function () { /* Say hello. */ var x = 'Hello!'; print(x); }).toSource() Will be converted to...
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If my interface must return Task what is the best way to have a no-operation implementation?

...mprove performance even more if you cache the already completed task since all instances of completed tasks are the same: public static class TaskExtensions { public static readonly Task CompletedTask = Task.FromResult(false); } With TaskExtensions.CompletedTask you can use the same instance ...
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filter for complete cases in data.frame using dplyr (case-wise deletion)

...data.frame for complete cases using dplyr? complete.cases with a list of all variables works, of course. But that is a) verbose when there are a lot of variables and b) impossible when the variable names are not known (e.g. in a function that processes any data.frame). ...
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What use is find_package() if you need to specify CMAKE_MODULE_PATH anyway?

...e. Now the software has a few dependencies. I compiled them myself and installed them on my system. 4 Answers ...
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Unicode characters in URLs

... in Firefox, the clipboard will hold the percent-encoded form (which is usually a good thing), but if you copy only a part of it, it will remain unencoded. share | improve this answer | ...
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Error - Unable to access the IIS metabase

After installing Visual Studio 2012 and opening my solution I get a series of errors in this form: 37 Answers ...
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Shortcut to create properties in Visual Studio?

I have seen some people creating properties in C# really fast, but how did they do it? 16 Answers ...
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Can you make valid Makefiles without tab characters?

... 2. The tab character is a very important part of the syntax of Makefiles. All command lines (the lines beginning with cc in our example) must start with tabs. After he made his change, line 2 didn’t, hence the error. “So what?” you ask, “What’s wrong with that?” There is nothi...