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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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How to create an empty file at the command line in Windows?
...omad mentions an original one:
C:\Users\VonC\prog\tests>aaaa > empty_file
'aaaa' is not recognized as an internal or external command, operable program or batch file.
C:\Users\VonC\prog\tests>dir
Folder C:\Users\VonC\prog\tests
27/11/2013 10:40 <REP> .
27/11/2013 10...
What does DIM stand for in Visual Basic and BASIC?
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Dim originally (in BASIC) stood for Dimension, as it was used to define the dimensions of an array.
(The original implementation of BASIC was Dartmouth BASIC, which descended from FORTRAN, where DIMENSION is spelled out.)
Nowadays, D...
IF… OR IF… in a windows batch file
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The zmbq solution is good, but cannot be used in all situations, such as inside a block of code like a FOR DO(...) loop.
An alternative is to use an indicator variable. Initialize it to be undefined, and then define it only if any one of the OR conditions is true. Then use ...
Get and Set a Single Cookie with Node.js HTTP Server
...console.log('Server running at http://127.0.0.1:8124/');
This will store all cookies into the cookies object, and you need to set cookies when you write the head.
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can we use xpath with BeautifulSoup?
...thon2, but Python3 is much preferred as 2 is being sunset (no longer officially supported) in 2020.
– wordsforthewise
Sep 30 '19 at 18:59
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What is the difference between the WPF TextBlock element and Label control? [duplicate]
Visually both of the following snippets produce the same UI. So why are there 2 controls..
Snippet1
6 Answers
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How to use/install gcc on Mac OS X 10.8 / Xcode 4.4
... Apple LLVM version 6.0 (clang-600.0.51) (based on LLVM 3.5svn) Target: x86_64-apple-darwin14.0.0 Thread model: posix So am I using gcc?
– Thomas
Dec 14 '14 at 16:11
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How can I convert string date to NSDate?
... */
let date = dateFormatter.dateFromString(/* your_date_string */)
For further query, check NSDateFormatter and DateFormatter classes of Foundation framework for Objective-C and Swift, respectively.
Swift 3 and later (Swift 4 included)
let dateFormatter = DateFormatter()...
Why is it not possible to extend annotations in Java?
...n types of arbitrary
external programs. Stub generators,
for example, fall into this category.
These programs will read annotated
classes without loading them into the
virtual machine, but will load
annotation interfaces.
So, yes I guess, the reason is it just KISS. Anyway, it seems th...